SSC CGL Tier 1 2012 General Awareness Questions with Solutions

Explanation

Plants are the primary producers in almost every ecosystem on Earth, serving as the foundational source of energy for all animal life. Through the process of photosynthesis, plants convert solar energy into chemical energy stored in the form of organic compounds like carbohydrates. Animals are heterotrophs, meaning they cannot synthesize their own food and must rely on the organic matter produced by autotrophs. Whether animals are primary consumers that eat plants directly or higher-level consumers that eat other animals, the energy they consume originates from plant life. If all plants were to die, the base of the food chain would be eliminated, leading to the total collapse of the energy pyramid and the subsequent death of all animals due to the unavailability of nutritional energy.

Explanation

Chlorination is a common method used for water disinfection and purification. It involves the addition of chlorine or chlorine-based compounds to water supplies to eliminate harmful microorganisms, including bacteria, viruses, and protozoa. This process is critical for preventing the spread of waterborne diseases such as cholera, dysentery, and typhoid. When chlorine is added to water, it reacts to form hypochlorous acid (HOCl) and hypochlorite ions, which are highly effective at penetrating the cell membranes of pathogens and disrupting their metabolic processes. By maintaining a residual amount of chlorine in the distribution system, it also ensures that the water remains protected from re-contamination until it reaches the consumer.

Explanation

Under Article 71(1) of the Constitution of India, the Supreme Court has the exclusive and original jurisdiction to inquire into and decide all doubts and disputes arising out of or in connection with the election of a President or Vice-President. The decision rendered by the Supreme Court in such matters is final. An election petition challenging the presidential election can be filed in the Supreme Court only after the election process is complete. Furthermore, if the election of a person as President is declared void by the Supreme Court, the acts performed by that person in the exercise of their official duties before the date of the court decision remain valid and are not invalidated.

Explanation

Bacterial growth in a liquid medium is commonly measured by turbidity using a spectrophotometer, which determines the optical density of the culture. An auxanometer is specifically used to measure the growth of plants, not bacteria.

Explanation

Apiculture refers to the scientific practice of rearing and managing honey bees for the production of honey and beeswax. The term is derived from the Latin word apis, which means bee. This activity involves the maintenance of bee colonies, typically in man-made hives, to facilitate the collection of honey, which is a high-energy food source, and beeswax, which is used extensively in the cosmetic and pharmaceutical industries. Beyond these products, honey bees are essential in agriculture as they serve as primary pollinators for many crops, thereby enhancing the productivity and quality of various fruits and seeds.

Explanation

Technological obsolescence is classified as an external factor of industrial sickness because it stems from advancements in the macro-environment, such as global research and development, the emergence of superior manufacturing processes, or shifts in industry standards. Since these scientific and market-driven changes occur independently of an individual firm's specific administrative or financial decisions, the source of the problem is exogenous. An industrial unit has no direct control over the pace at which new technologies are invented or adopted by the wider industry, making it a challenge imposed by the external economic and competitive landscape.

Explanation

Article 76 of the Constitution of India provides for the office of the Attorney General for India, who is appointed by the President. As the highest law officer in the country, the Attorney General serves as the chief legal advisor to the Union Government and is responsible for performing duties of a legal character assigned by the President. This role includes representing the Government of India in all legal proceedings in the Supreme Court and various High Courts. The Attorney General holds the right of audience in all courts within the territory of India and possesses the right to participate in the proceedings of both Houses of Parliament without the right to vote.

Explanation

Carbon monoxide is a highly toxic, colorless, odorless, and tasteless gas that is primarily produced by the incomplete combustion of fossil fuels. It is considered one of the most hazardous air pollutants because of its severe physiological impact on human health. When inhaled, carbon monoxide enters the bloodstream and binds with hemoglobin to form carboxyhemoglobin (HbCO). The affinity of hemoglobin for carbon monoxide is approximately 200 to 250 times greater than its affinity for oxygen. This preferential binding prevents hemoglobin from transporting oxygen to the body's tissues and vital organs. Even at relatively low concentrations, this displacement leads to hypoxia, causing symptoms such as headaches, dizziness, and impaired judgment, while high concentrations can result in rapid unconsciousness and death due to oxygen starvation.

Explanation

Urea is synthesized in the liver through the biochemical process known as the urea cycle or ornithine cycle. While the kidneys are responsible for filtering and excreting urea from the blood, they do not produce it.

Explanation

Growing regional imbalances refer to the unequal distribution of economic development, infrastructure, and investment across different geographical areas within a state. When a specific region perceives that it is being systematically neglected in terms of budgetary allocations, public sector employment, and industrial growth compared to a more dominant region, it creates a sense of relative deprivation among the local population. This economic disparity serves as the primary driver for political mobilization, as residents believe that administrative autonomy through the creation of a separate state is the only way to ensure equitable resource allocation and tailored developmental policies. Historically, movements for states like Telangana or Jharkhand were deeply rooted in the grievance that their natural resources or revenue were being utilized to develop other regions while their own areas remained underdeveloped.

Explanation

Vikramshila University was established by King Dharmapala of the Pala dynasty during the late 8th or early 9th century AD. Located at Antichak in the Bhagalpur district of modern-day Bihar, it was founded to serve as a premier center for Buddhist learning, specifically focusing on Vajrayana Buddhism. It quickly rose to prominence as one of the most important educational institutions in ancient India, often considered a major contemporary to Nalanda. King Dharmapala provided extensive royal patronage to the university, overseeing the construction of a large monastery and numerous temples. Under the Pala rulers, the institution attracted scholars from across Asia and produced many eminent teachers, including the famous monk Atisha Dipankara, who was instrumental in spreading Buddhist teachings to Tibet.

Explanation

The classification of a government as federal or unitary is determined by the constitutional distribution of powers between the central authority and the regional or state authorities. In a federal system, sovereignty is constitutionally divided between a central government and various constituent units, such as states or provinces, each being supreme within its own sphere of jurisdiction. In a unitary system, all sovereign power is vested in the central government, and any subnational administrative units exercise only those powers specifically delegated to them by the center. Thus, the nature of the legal and political relationship between the center and the states is the fundamental criterion used to distinguish these two forms of governance.

Explanation

Vyakarana is one of the six Vedangas, which are the auxiliary disciplines of Vedism developed in ancient India to support the study and preservation of the Vedas. It focuses specifically on grammar and linguistic analysis, establishing the rules for the correct formation and usage of words in the Sanskrit language. The most celebrated work in this field is Panini's Ashtadhyayi, which provides a comprehensive and scientific framework for Sanskrit grammar, ensuring the structural integrity of the sacred hymns and facilitating their accurate interpretation.

Explanation

New Zealanders are popularly known as Kiwis. This nickname is derived from the kiwi, a unique flightless bird that is endemic to New Zealand and serves as a national symbol. The term gained international recognition during World War I, when New Zealand soldiers were referred to as Kiwis because of the kiwi bird images featured on their regalia and military badges. Over time, the name evolved from a military designation into a common and affectionate demonym for all citizens of the country.

Explanation

The Palitana Temples are located on the Shatrunjaya Hills near the city of Palitana in the Bhavnagar district of Gujarat. These temples are considered the holiest pilgrimage site for the Svetambara Jain community. The complex contains approximately 863 marble-carved temples, the most prominent of which is dedicated to Adishwara, the first Jain Tirthankara. The site is unique because it is the only mountain in the world that has more than 900 temples, and according to Jain tradition, it is the place where Adinatha performed his first sermon. The climb to the main temple complex involves navigating more than 3,500 stone steps.

Explanation

Parliamentary government is fundamentally based on the principle of collective responsibility of the executive to the legislature. Political parties serve as the vital link that enables this system to function by organizing the competition for power and providing a coherent majority to form the government. They ensure that the executive is drawn from the legislature and maintains its confidence through party discipline and shared policy objectives. Without political parties, it would be impossible to establish a stable administration or a structured opposition, both of which are central to the parliamentary mechanism of governance and accountability.

Explanation

El Nino is a climatic cycle in the Pacific Ocean with a global impact on weather patterns. It is characterized by the weakening of the easterly trade winds, which normally push warm surface water toward the western Pacific. When these winds slacken, the warm water accumulated in the western Pacific begins to flow eastward toward the coast of South America. This eastward movement is an intensification and southward extension of the Equatorial Counter Current. As this warm counter current reaches the coasts of Ecuador and Peru, it overrides the cold surface waters, leading to a significant rise in sea surface temperatures and suppressing the normal upwelling of nutrient-rich cold water. This shift in the Equatorial Counter Current is the primary physical mechanism that defines the onset of an El Nino event.

Explanation

Electronic Voting Machine (EVM) is the official term for the electronic device used to record and count votes in elections. In India, EVMs were designed by the Election Commission of India in collaboration with Bharat Electronics Limited and Electronics Corporation of India Limited. The primary purpose of these machines is to modernize the voting process, prevent electoral fraud such as booth capturing or ballot stuffing, and ensure a faster and more accurate counting of votes compared to traditional paper ballots. The system consists of a control unit, operated by the polling official, and a balloting unit, placed inside the voting compartment for the voter. EVMs were first used in 1982 in the Paravur Assembly constituency of Kerala and were implemented nationwide for the 2004 General Elections.

Explanation

JDBC is a standard Java application programming interface (API) that defines how a Java application can access a database. It provides methods for querying and updating data in a relational database management system (RDBMS) using Structured Query Language (SQL). By using JDBC, developers can write database applications that are independent of the specific database platform, as the API acts as a middle layer between the Java code and the database driver. It includes a set of classes and interfaces that handle connection management, statement execution, and result set processing, allowing for seamless integration of database functionality within Java environments.

Explanation

Milk of magnesia is a white, alkaline suspension of magnesium hydroxide, represented by the chemical formula Mg(OH)₂, in water. It derives its name from its milk-like appearance, which is a result of the limited solubility of magnesium hydroxide in aqueous solutions. In medicine, it is widely utilized as an antacid to neutralize hydrochloric acid in the stomach and as an osmotic laxative to treat constipation. When consumed, the hydroxide ions react with the hydrogen ions of the gastric acid to form water and magnesium chloride, thereby reducing acidity.

Explanation

Pila globosa, often referred to in biological studies as a bio-filter, is a freshwater snail known for its ability to bioaccumulate heavy metals from its environment. It is particularly effective at absorbing and sequestering Cadmium (Cd) within its internal organs, such as the digestive gland, gills, and mantle. Through this process of bioaccumulation, the organism removes the toxic metal from the water column, effectively acting as a biological filter that reduces the concentration of Cadmium pollution in aquatic ecosystems. Its physiological resilience and high uptake capacity make it a significant subject for bioremediation and the monitoring of heavy metal contamination in ponds and lakes.

Explanation

The Food Corporation of India (FCI) is a statutory body established under the Food Corporations Act of 1964 to implement the food policy of the Government of India. Its primary mandate is the procurement of food grains at Minimum Support Price (MSP) from farmers, maintaining strategic buffer stocks for food security, and distributing grains through the Public Distribution System (PDS). Unlike the other listed organizations, which are specialized financial institutions designed to provide credit and development finance to specific sectors, FCI is an operational and logistical agency. It does not function as a bank or a lending institution and does not provide financial assistance or credit facilities to food grains merchants.

Explanation

The word Secular was added to the Preamble of the Constitution of India through the 42nd Constitutional Amendment Act, 1976. This amendment, enacted during the Prime Ministership of Indira Gandhi, introduced three new words to the Preamble: Socialist, Secular, and Integrity. Prior to this change, the Preamble described India as a Sovereign Democratic Republic. The formal inclusion of the term Secular explicitly codified the constitutional philosophy that the State has no official religion and treats all religions with equal respect and neutrality, a concept already reflected in the Fundamental Rights under Articles 25 to 28. To date, the 42nd Amendment remains the only instance where the Preamble of the Indian Constitution has been amended.

Explanation

Plaster of Paris is chemically known as calcium sulphate hemihydrate, which is represented by the chemical formula CaSO₄ · ½H₂O. The term hemihydrate indicates that half a molecule of water of crystallization is associated with each formula unit of calcium sulphate. In practical molecular terms, this means two units of calcium sulphate share one molecule of water, written as (CaSO₄)₂ · H₂O. It is manufactured by heating gypsum, which is calcium sulphate dihydrate (CaSO₄ · 2H₂O), to a controlled temperature of about 373 K or 100 °C. At this temperature, gypsum loses three-fourths of its water of crystallization to form the hemihydrate. Upon mixing with water, Plaster of Paris undergoes a rehydration reaction to form a hard solid mass of gypsum once again.

Explanation

The Sutlej River is a major tributary of the Indus system that originates from the Rakshas Tal near Lake Mansarovar in Tibet. It enters Indian territory at the Shipki La pass, which is located in the Kinnaur district of Himachal Pradesh. The river travels through several districts of the state, including Kinnaur, Shimla, Mandi, and Bilaspur, before exiting into the plains of Punjab. In Himachal Pradesh, the Sutlej is characterized by its steep gradient and deep gorges as it cuts through the Himalayan ranges. It serves as a critical source for irrigation and hydroelectric power generation, most notably through the Bhakra Dam project located in the Bilaspur district of the state.

Explanation

The acidity or alkalinity of a liquid is determined by its pH value, which represents the concentration of hydrogen ions (H^+) in the solution. A pH meter is the standard scientific instrument used to measure this activity, typically providing a numerical value on a scale from 0 to 14. On this scale, a pH level below 7 indicates that the solution is acidic. Since rain acidity is defined by the presence of substances like sulfuric and nitric acids that release hydrogen ions, a pH meter is the required tool to quantify the degree of acidity in rainwater samples.

Explanation

Customs duties are taxes levied on goods imported into or exported from India. Under the distribution of revenue between the Union and the States as laid out in the Seventh Schedule (Entry 83 of the Union List), customs duty is collected and retained by the Central Government. Unlike Income Tax and Union Excise Duties, which were traditionally shared with the states under the constitutional framework of Articles 270 and 272, customs duty was historically excluded from the divisible pool. While subsequent constitutional amendments like the 80th Amendment Act of 2000 restructured the sharing of taxes, customs duty remained a primary revenue source that was not subject to mandatory distribution to the states in the same manner as other shared taxes.

Explanation

Water hyacinth (Eichhornia crassipes) is a free-floating perennial aquatic plant native to tropical South America. It is widely recognized as one of the most productive and fastest-growing plants on Earth. The species reproduces extremely rapidly through vegetative propagation using stolons, which allows it to double its biomass and surface area coverage in approximately one to two weeks under optimal nutrient and temperature conditions. This aggressive growth rate enables the plant to quickly colonize vast areas of water, forming thick, interlocking mats that disrupt aquatic ecosystems and human activity.

Explanation

ROM, EPROM, and EEPROM are all types of non-volatile memory, meaning they retain their stored data even when the power supply is disconnected. Since all three options share this characteristic, the most accurate choice is All the above.

Explanation

Sarva Shiksha Abhiyan (SSA) is the flagship programme of the Government of India launched in 2001 to achieve the Universalization of Elementary Education (UEE). It is a centrally sponsored scheme implemented in partnership with state governments to provide free and compulsory education to all children in the 6 to 14 age group. By 2012, the programme had been scaled up to cover all districts across the country to meet the mandates of the Right of Children to Free and Compulsory Education (RTE) Act, 2009. It focuses on opening new schools, providing additional classrooms, toilets, and drinking water facilities, as well as recruiting teachers to maintain an appropriate pupil-teacher ratio in every administrative district of India.

Explanation

Captain William Hawkins arrived at the port of Surat in August 1608 aboard the ship Hector, representing the English East India Company. He traveled to the Mughal court at Agra in 1609 to meet Emperor Jahangir, carrying a letter from King James I of England to seek permission for trade and the establishment of a factory. Hawkins was able to communicate directly with the Emperor in Turkish, which greatly impressed Jahangir. As a result of this successful interaction, the Emperor appointed him as a mansabdar with a rank of 400 and conferred upon him the title of English Khan, marking the first significant diplomatic encounter between the Company and the Mughal Empire.

Explanation

The sex ratio is a critical demographic indicator that represents the number of females for every 1,000 males in a population. According to the 2011 Census of India, the sex ratio stood at 940 based on the provisional data released by the Registrar General and Census Commissioner. This figure marked an increase from the 2001 Census, which had recorded a sex ratio of 933. While the final 2011 Census reports eventually updated the specific count to 943, the figure of 940 was the primary statistic recognized in official documentation and academic materials immediately following the census operations.

Explanation

Jean-Baptiste Lamarck proposed the Law of Use and Disuse as a fundamental part of his theory of evolution, published in his 1809 work, Philosophie Zoologique. This principle suggests that the frequent and continuous use of any organ gradually strengthens, develops, and enlarges that organ in proportion to the duration of its use. Conversely, the permanent disuse of an organ weakens and deteriorates it, diminishing its functional capacity until it eventually disappears. Lamarck hypothesized that these physical modifications acquired by an individual during its lifetime are inherited by its offspring, driving the evolutionary adaptation of a species to its environment.

Explanation

Kapil Dev was named the Wisden Indian Cricketer of the Century in 2002, a title recognizing the most impactful Indian player of the 1900s. This honor was primarily bestowed due to his historic achievement in captaining India to its first World Cup title in 1983 and his unprecedented success as an all-rounder. Kapil Dev was the first cricketer in the world to reach the milestone of 400 Test wickets and finish a career with over 5,000 Test runs. He held the world record for the highest number of Test wickets (434) at the time of his retirement in 1994. His selection for this award placed him at the pinnacle of Indian cricket history for his contributions throughout the twentieth century.

Explanation

The Atlas V (Atlas 5) is a heavy-lift launch vehicle that has been instrumental in NASA's Mars exploration programs. Most notably, an Atlas V 541 rocket launched the Mars Science Laboratory (MSL) mission, carrying the Curiosity rover, on November 26, 2011. Additionally, the Atlas V was used to launch the Mars Reconnaissance Orbiter (MRO) in 2005, which provides critical high-resolution data and imagery of the Martian surface and atmosphere. Because these missions rely on the Atlas V to reach their destination, the rocket is directly associated with the acquisition of scientific information about Mars.

Explanation

The Wanchoo Committee, officially known as the Direct Taxes Enquiry Committee, was constituted by the Government of India in 1970 under the chairmanship of Justice Niranjan Nath Wanchoo. Its primary objective was to investigate the causes of tax evasion and the proliferation of black money in the Indian economy. The committee submitted its final report in 1971, recommending various structural changes to the direct tax system, including measures to simplify tax laws, strengthen tax administration, and implement more effective ways to unearth and prevent the generation of unaccounted wealth.

Explanation

Carbohydrates are organic compounds fundamentally composed of carbon (C), hydrogen (H), and oxygen (O) atoms. Their name is derived from the observation that their elemental composition often follows the general formula Cₙ(H₂O)ₘ, representing a hydrate of carbon where the ratio of hydrogen to oxygen is 2:1, identical to that of water. These molecules include simple sugars like glucose, which has the formula C₆H₁₂O₆, as well as complex polymers such as starch and cellulose. They play critical roles in biological systems by providing chemical energy for cellular metabolism and offering structural support to plants and various microorganisms through these three core elements.

Explanation

The growth of a bacterial population through binary fission follows a geometric progression. The total number of bacteria produced after a certain period can be determined using the formula N = N₀ × 2ⁿ, where N₀ represents the initial number of bacteria and n represents the total number of divisions or generations.

In this scenario, the total duration is 2 hours, which is equivalent to 120 minutes. Since the bacterium divides once every 20 minutes, the number of generations n is calculated by dividing the total time by the generation time: n = 120 / 20 = 6.

Starting with a single bacterium cell (N₀ = 1), the population after 6 generations is calculated as 1 × 2⁶. Expanding this power of two, we get 2 × 2 × 2 × 2 × 2 × 2 = 64. Therefore, 64 bacteria are formed at the end of the two-hour period.

Explanation

The Kyoto Protocol is an international treaty that extends the 1992 United Nations Framework Convention on Climate Change (UNFCCC) by committing state parties to reduce greenhouse gas emissions. Adopted in 1997 and entering into force in 2005, the protocol established legally binding obligations for industrialized countries to reduce their emissions of six greenhouse gases. The first commitment period of the agreement specifically targeted the years 2008 to 2012, during which period the participating countries aimed to reduce their collective emissions by an average of 5.2 percent relative to 1990 levels. This agreement was the primary international framework for climate action during the specified timeframe.

Explanation

The ear drum, or tympanic membrane, is a delicate structure that separates the outer ear from the middle ear and is sensitive to changes in atmospheric pressure. High-intensity sounds like thunder generate sudden, powerful pressure waves in the air. The Eustachian tube connects the middle ear cavity to the nasopharynx at the back of the throat. By opening the mouth, a person allows the external air pressure to travel through the throat and the Eustachian tube to the inner side of the ear drum. This mechanism ensures that the pressure exerted on the outer surface of the membrane is balanced by equal pressure on the inner surface, preventing potential rupture or injury to the ear drum from the sudden acoustic shock.

Explanation

Water exhibits anomalous expansion where its density is maximum and its volume is minimum at 4 degrees Celsius. When heated from 0 to 4 degrees Celsius, the volume of water decreases, and as the temperature rises further from 4 to 10 degrees Celsius, the volume increases.

Explanation

The Chambal River is a major tributary of the Yamuna River and forms part of the greater Gangetic drainage system. It originates in the Vindhya Range at Janapav, south of Mhow in the Indore district of Madhya Pradesh. The river flows north-northeast through Madhya Pradesh, enters Rajasthan through a gorge near Chaurasgarh, and continues past Kota. It subsequently forms the boundary between Rajasthan and Madhya Pradesh for a significant stretch before entering Uttar Pradesh. Finally, the Chambal joins the Yamuna River in the Etawah district of Uttar Pradesh. Its entire course is thus contained within the states of Madhya Pradesh, Rajasthan, and Uttar Pradesh.

Explanation

According to the 2011 Census of India, Uttar Pradesh is the most populous state in the country with a population of approximately 19.98 crore (199,812,341). This accounted for about 16.5 percent of India's total population at the time. The state's vast geographical area within the fertile Indo-Gangetic plain supports a high density of inhabitants, making its population comparable to that of the world's fifth most populous nation, Brazil, during that period.

Explanation

The state of Jhansi was annexed by the British East India Company in 1854 through the application of the Doctrine of Lapse. This policy, extensively used by Governor-General Lord Dalhousie between 1848 and 1856, mandated that any princely state under the paramountcy of the British would be annexed if its ruler died without a natural male heir. Following the death of Raja Gangadhar Rao in 1853, the British refused to recognize the legitimacy of his adopted son, Damodar Rao, as the successor to the throne. Consequently, the British authorities declared that the sovereignty of the state had lapsed to the paramount power, leading to the formal incorporation of Jhansi into the British Empire.

Explanation

The book A Better India, A Better World, published in 2009, is authored by N.R. Narayana Murthy, the co-founder and former chairman of Infosys. The work is a collection of speeches he delivered over several years, focusing on his vision for India's development. In the book, Murthy addresses critical issues such as poverty, corruption, and the need for ethical leadership and corporate governance. He argues that India can achieve global prominence by fostering a culture of hard work, discipline, and meritocracy, while leveraging information technology and globalization to drive economic growth and social equity.

Explanation

Simple Goitre is a condition characterized by the abnormal enlargement of the thyroid gland, which is located at the base of the neck. The primary cause of this condition is a deficiency of dietary iodine, a mineral essential for the synthesis of thyroid hormones such as thyroxine. When iodine levels are insufficient, the thyroid gland cannot produce an adequate amount of these hormones. In response, the pituitary gland secretes increased levels of Thyroid-Stimulating Hormone (TSH) to stimulate the thyroid. This prolonged overstimulation causes the gland's tissues to swell and expand as it attempts to compensate for the deficiency, resulting in the visible enlargement known as a goitre.

Explanation

According to the law of conservation of mechanical energy, the total energy of a body remains constant if only conservative forces like gravity are acting on it. The total mechanical energy E of a body of mass m at the top of a tower of height h is the sum of its potential energy and its kinetic energy:

E = mgh + ½mv²

Both bodies x and y have the same mass m, are at the same height h, and are thrown with the same initial speed v. Consequently, they both possess the exact same amount of total mechanical energy at the start. As they fall, their potential energy is converted into kinetic energy. When they reach the ground, their height is zero, meaning all the initial mechanical energy has been converted into final kinetic energy K_f:

K_f = mgh + ½mv²

Since all variables in this expression are identical for both bodies, they will strike the ground with the same kinetic energy, regardless of the direction in which they were initially thrown.

Explanation

SONAR, which stands for Sound Navigation and Ranging, is a technique that uses sound propagation to navigate, communicate with, or detect objects on or under the surface of the water. It operates by emitting ultrasonic waves from a transducer into the sea. When these sound waves encounter a submerged object, they reflect back as an echo to a receiver. By measuring the time interval between the transmission of the pulse and the reception of the echo, and knowing the speed of sound in water, the distance and position of the object can be accurately determined. Since electromagnetic waves like radio waves are rapidly absorbed by water, sound waves are the most effective means for underwater detection and ranging.

Explanation

The Tropic of Capricorn is located at 23½° S latitude, marking the southernmost position where the Sun can be directly overhead. The International Date Line follows the 180° meridian through the Pacific Ocean to separate two consecutive calendar days. In contrast, 66½° N latitude identifies the Arctic Circle, and 0° longitude identifies the Prime Meridian. Thus, the pairings in (ii) and (iii) are incorrectly defined.

Explanation

In economic theory, a movement along the demand curve signifies a change in the quantity demanded of a commodity specifically in response to a change in its own price, assuming all other factors remain constant (ceteris paribus). According to the Law of Demand, an inverse relationship exists between price and quantity demanded. When the price of the commodity falls, the quantity demanded increases, leading to a downward movement along the curve known as an expansion of demand. Conversely, when the price rises, the quantity demanded decreases, resulting in an upward movement along the curve known as a contraction of demand. This distinguishes price changes from other determinants which would otherwise cause the entire demand curve to shift.