1.

What is/are true?

1. Mahogany, Rosewood and Ebony trees are found in Tropical Deciduous Forest.

2. Tropical Deciduous Forests are dense and multi-layered in structure.

(a) Only 1 is true.

(b) Only 2 is true.

(c) 1 & 2 are true

(d) Neither 1 nor 2 is true 

2.

(1) Kuiper Belt is a sparsely occupied ring of icy bodies.

(2) Oort cloud is the boundary of the Sun''s gravitational influence.

Which of the above is/are incorrect?.

(a) Only 1

(b) Only 2

(c) Both 1 and 2

(d) Neither 1 Nor 2

3.

What are “anyons” seen in news?.

(a) Glacial lakes

(b) Sand dunes

(c) Fundamental particles that make up the whole universe

(d) Specialised cells discovered in pancreas and is found to metabolise lipids

4.

Consider the following statements:

1. Io is the most volcanically active object in the solar system.

2. Io is slightly larger than the Earth’s Moon.

Which of these statements is/are correct?

(a) 1 and 2 are correct

(b) Only 1 is correct

(c) Only 2 is correct

(d) None is correct

5.

Consider the various sources of information about the interior of the earth:

1.     Earth magnetism

2.     Gravitational force

3.     Meteors

4.     Seismic Activity

5.     Mined Rocks

6.     Volcanoes

Which one of the above sources are direct source of information about the Interior of the Earth?

(a) 3, 4, 5 and 6

(b) 1, 2 and 4

(c)  2 and 4 only

(d) 1, 3, 5 and 6

6.

Match the following.

Select the correct code from the options given below 

(a) 1-I, 2-III, 3-IV

(b) 1-II, 2-III, 3-IV

(c) 1-I, 2-IV, 3-III

(d) 1-II, 2-IV, 3-III

7.

What is/are true?

1. A photon interacts with Higgs field.

2. An electron does not interact with Higgs field.

(a) Only 1 is true.

(b) Only 2 is true.

(c) 1 & 2 are true

(d) Neither 1 nor 2 is true   

8.

The continuation of La Nina conditions spanning over two consecutive years is called

(a) ‘Double Dip’ La Nina.

(b) ‘Half Dip’ La Nina.

(c) ‘Julian’ La Nina.

(d) ‘Modoki’ La Nina.

9.

The main reason that the earth experiences highest temperatures in the subtropics in the northern hemisphere rather than at the equator is

(a) Subtropical areas tend to have less cloud cover than equatorial areas.

(b) Subtropical areas have longer day hours in the summer than the equatorial.

(c) Subtropical areas have an enhanced “green house effect” compared to equatorial areas.

(d) Subtropical areas are nearer to the oceanic areas than the equatorial locations.

10.

Transfer of surplus heat from the lower latitudes to higher latitudes is done by

1. Ocean currents

2. Planetary winds

3. Tides

4. Waves

(a) 1 and 2 only

(b) 2, 3 and 4 only

(c) 1 and 3 only

(d) 1, 2, 3 and 4 only

11.

What is/are true?

1. HFC doesn’t harm ozone.

2. The biggest emitters of HFCs are mobile air conditioning (MAC) systems in cars.

(a) Only 1 is true.

(b) Only 2 is true.

(c) 1 & 2 are true

(d) Neither 1 nor 2 is true 

12.

Which of the following are members of Arctic council?

1. Netherland

2. Finland

3. United Kingdom

4. Poland

5. Russia

(a) 1, 2 & 4

(b) 1, 2, 3 & 5

(c) 2 & 5

(d) 2, 3 & 5

13.

Which of the following is/are correct about shifting cultivation?

1. It involves no ploughing.

2. It involves crop rotation.

3. It is combined with transhumance.

(a) 1 only

(b) 1 and 2 only

(c) 2 and 3 only

(d) 1 and 3 only

14.

Which of the following is/are westerlies?.

1. Roaring Forties

2. Furious Fifties

3. Screeching Sixties

(a) 1, 2 & 3

(b) Only 3

(c) Only 1 & 2

(d) None of these

15.

Which of the following statements is not true w.r.t. Wegener’s Continetal Drift Hypothesis?.

(a) Pangaea was surrounded by Panthalassa.

(b) The gold-bearing veins present in Brazil discredit the Wegener’s Continetal Drift Hypothesis.

(c) The interpretations that Lemurs occur in India, Africa, and Madagascar support Wegener’s Hypothesis.

(d) Tethys divided the Pangaea.

16.

Which of the following statements is/are true?.

(1) The Himalayas occur along a convergent boundary where Continental crust meets Continental crust.

(2) Continental crust is thicker than the oceanic crust.

(a) Only 1

(b) Only 2

(c) Both 1 and 2

(d) None of the above

17.

Which one of the following pairs of straits and the countries they separate is correctly matched?

1. Gibraltar Strait - Spain and Morocco

2. Makassar Strait - Sumatra and Malaysia

3. Magellan Strait - Chile and Tiera del Fuego

4. Bass Strait - Australia and Tasmania

(a) 1 and 4 only

(b) 2 and 3 only

(c) 1, 3 and 4 only

(d) 1, 2, 3 and 4 only

18.

(1) Tides are high waves but with low energy while sea waves are low waves with high energy.

(2) Tides are originated due to interactions of the sun and the moon with ocean surfaces while sea waves are generated by wind drag.

Which of the above is/are incorrect?.

(a) Only 1

(b) Only 2

(c) Both 1 and 2

(d) Neither 1 Nor 2

19.

CFCs eat away ozone only if

1. light is present

2. air is cold enough

(a) Only 1

(b) Only 2

(c) 1 & 2

(d) Neither 1 nor 2

20.

Consider the following statements:

1. 9 Degree Channel separates islands of Minicoy and Maldives.

2. 8 Degree Channel separates the island of Minicoy from the main Lakshadweep archipelago.

Which of the statements given above is/are correct?.

(a) 1 only

(b) 2 only

(c) Both 1 and 2

(d) Neither 1 nor 2

21.

Djibouti Code of Conduct/ Jeddah Amendment (DCoC/JA), is related to

(a) Global Ethical Governance

(b) Piracy issues of ships

(c) Diplomatic missions

(d) Refugee crisis

22.

Incase the International Date Line was a straight line, which of the following islands would have experienced a two-date problem within the same time zone?

1. Wrangel Island

2. Aleutian Islands

3. Kiribati islands.

(a) 1, 2 & 3

(b) Only 3

(c) Only 1 & 2

(d) None of these

23.

Which of the following are created when subduction between a plate carrying continental crust and a plate carrying oceanic crust happen?.

(a) Oceanic trenches

(b) Dip faults

(c) Tsunamis

(d) Deep sea magmas

24.

Laughing gas is emitted by/during

1. Lightning

2. Soil Surface

3. Deforestation

4. Waste water tretament

(a) 1 and 4 only

(b) 1, 2, 3 and 4

(c) 1, 2 and 3 only

(d) 2 and 3 only

25.

The Earth without rotational movement would result into.

1. no sun-rise and sun-set.

2. no occurrence of day and night cycle.

3. only one season.

(a) 1 & 2

(b) 1, 2 & 3

(c) Only 2

(d) Only 1

1.

D   

2.

Solar systems can also have more than one star. These are called binary star systems if there are two stars or multi-star systems if there are three or more stars. Our solar system is located in an outer spiral arm of the vast Milky Way galaxy. Our solar system orbits the centre of the Milky Way Galaxy at about 828,000 km/h. Our solar system takes about 230 million years to complete one orbit around the galactic centre.  The solar system is believed to have been formed about 4.6 billion years ago. The solar system also includes the Kuiper Belt that lies past Neptune''s orbit. This is a sparsely occupied ring of icy bodies. This is almost all smaller than the dwarf planet Pluto.  Beyond the fringes of the Kuiper belt is the Oort cloud. This giant spherical shell surrounds our solar system.

·    The Oort cloud is made up of icy pieces of space debris. It is orbiting our Sun as far as 1.6 light years away. This shell of material is thick, extending from 5,000 astronomical units to 100,000 astronomical units. One astronomical unit (AU) is the distance from the Sun to Earth, or about 150 million kilometre. The Oort cloud is the boundary of the Sun''s gravitational influence, where orbiting objects can turn around and return closer to our Sun.

D

3.

https://indianexpress.com/article/technology/science/neutrinos-tb-bacteria-quake-resistant-buildings-young-scientists-8941527/

B 

4.

Io is in Jupiter.

https://indianexpress.com/article/technology/science/nasa-juno-spacecraft-jupiter-io-8942227/

A

5.

Direct Sources of information about the Earth’s Interior

·      Deep earth mining and drilling reveal the nature of rocks deep down the surface.

·      But as mining and drilling are not practically possible beyond a certain depth, they don’t reveal much information about the earth’s interior.

·      Mponeng gold mine (deepest mine in the world) and TauTona gold mine (second deepest mine in the world) in South Africa are deepest mines reaching to a depth of only 3.9 km.

·      And the deepest drilling is only about 12 km deep hole bored by the Soviet Union in the 1970s over the Kola Peninsula.

·      Volcanic eruption forms another source of obtaining direct information.

Indirect Sources of information about the Earth’s Interior

·      Increase in pressure and temperature with depth

·      Seismic waves

·      Meteorites

·      Gravitation

·      Magnetic field

B

6.

https://timesofindia.indiatimes.com/home/science/scientists-in-uk-set-fusion-record-latest-news/articleshow/107529777.cms 

https://www.thehindu.com/sci-tech/science/in-a-doughnut-in-japan-unlocking-the-power-of-the-sun/article67873782.ece 

D

7.

https://indianexpress.com/article/explained/explained-sci-tech/peter-higgs-god-particle-9262142/

d

8.

https://www.downtoearth.org.in/news/climate-change/-double-dip-la-nina-has-formed-for-second-year-in-a-row-says-noaa-79758  

A

9.

The climate of any region is influenced by two major factors

1.      Insolation (Temperature)

2.      Precipitation (Rainfall)

And these two factors are determined by the latitudes ( imaginergy lines dividing Earth horizontally).

Generally, it is assumed that the temperature decreases from the equator toward the poles (i.e it is assumed that the temperature is maximum at the equator and minimum at the poles) because sunlight falls directly on the equator and slantingly over the tropics and poles.

BUT, the temperature at Equator is lower than at the sub-tropics.

This is because of the following reasons:

1.   The equatorial region mostly comprised of seas and oceans, so when the sunrays fall over it, the ocean water gets heated up and led to vapourisation which finally results in the formation of clouds. And these clouds alongwith low pressure area lead to rain, which makes the climate here warm and humid, with rainfall throughout the year.

2.   Though it’s true that the Equator gets the most sunlight, but good portion of this sunlight is used up in evaporating water from seas and other water bodies, rather than increasing the actual temperature of the region. Thus leading to low diurnal range ( i.e temperature difference between day and night is very less).

3.   And then clouds formed due to the evaporation of water, act as barriers obstructing the direct fall of sunlight; this also helps in not increasing the temperature of Equatorial region.

Countries like Indonesia, Malaysia, Papua New Guinea, Brunei etc. experiences equatorial climate .

1)       As far as Tropical countries are concerned ( including India), due to more landmass and lesser sea surface over the tropical region, the temperature is higher. This phenomenon of high temperature is more prominent in inland area (which has no access to sea).

2)       As far as specifically India is concerned, despite being a peninsula (i.e surrounded by water body on three sides, here Arabian sea, Bay of Bengal and Indian Ocean) is hot because of its huge landmass . The coastal areas of India, no doubt are warmer but the inlands are hotter. Therefore, India is hotter than equatorial countries.

Due to this reason also, most of the hot deserts are found in the tropical regions.

A

10.

·   The earth receives a certain amount of Insolation (short waves) and gives back heat into space by terrestrial radiation (longwave radiation). Through this inflow and outflow of heat, the earth maintains a constant temperature and this phenomenon is referred to as the heat budget of the earth.

·   The Sun doesn’t heat the Earth evenly. Because the Earth is a sphere, the Sun heats equatorial regions more than polar regions. The atmosphere and ocean work non-stop to even out solar heating imbalances through evaporation of surface water, convection, rainfall, winds, and ocean circulation.

·   This coupled atmosphere and ocean circulation maintain the temperature on earth in the following ways:

·   The climate’s heat engine must not only redistribute solar heat from the equator toward the poles but also from the Earth’s surface and lower atmosphere back to space.

·   When the flow of incoming solar energy is balanced by an equal flow of heat to space, Earth is in radiative equilibrium, and global temperature is relatively stable.

·   Regions within the equator and 40° N and S latitudes receive abundant sunlight and hence they are energy surplus regions. Regions beyond 40° N and S latitudes lose more heat than that gained from sunlight and hence they are energy deficit regions.

·   The atmosphere (planetary winds) and the oceans (ocean currents) transfer excess heat from the tropics (energy surplus region) towards the poles (energy deficit regions) making up for heat loss at higher latitudes.

·   Most of the heat transfer takes place across the mid-latitudes (30° to 50°)[more while studying jet streams and cyclones], and hence much of the stormy weather is associated with this region.

·   Thus, the transfer of surplus energy from the lower latitudes to the deficit energy zone of the higher latitudes maintains an overall balance over the earth’s surface.

A

11.

The biggest emitters of HFCs are mobile air conditioning (MAC) systems in cars (66% of all HFC emissions according to 2002 data from US EPA and ADEME); followed by commercial refrigeration, and particularly supermarket refrigeration (23%); and finally stationery air conditioning systems (6%) such as found in retail units and offices. HFC is a potent greenhouse gas. US is desperate to bring HFC under ambit of Montreal protocol despite of the fact that it has no implications for Ozone layer. India is pushing for its inclusion under framework to be agreed at Paris conference, which will be more stringent selectively for developed countries (unlike Montreal protocol).

https://indianexpress.com/article/explained/explained-climate/ozone-hole-filling-up-now-antarctica-montreal-protocol-greenhouse-gases-climate-change-8374040/

C  

12.

Arctic council has eight member countries: Canada, Denmark, Finland, Iceland, Norway, Russia, Sweden, and the United States. China, India, Italy, Japan, Singapore, South Korea, Netherlands, Poland, Spain, United Kingdom, France, Germany are observers of Artic council.

The Arctic Council was created with the signing of the Ottawa Declaration on 19 September 1996 in Canada. India was granted observer status at the Kiruna Ministerial Meeting in 2013.

https://www.thehindu.com/sci-tech/energy-and-environment/explained-what-is-happening-to-arctic-sea-ice/article66955260.ece

https://www.thehindu.com/news/international/russias-isolation-takes-toll-on-arctic-climate-science/article67647705.ece#:~:text=The%20Arctic%20Council%20is%20a,some%20studies%20have%20been%20delayed.

c

13.

·        Shifting cultivation is an agricultural system in which plots of land are cultivated temporarily, then abandoned and allowed to revert to their natural vegetation while the cultivator moves on to another plot.

·        The period of cultivation is usually terminated when the soil shows signs of exhaustion or, more commonly, when the field is overrun by weeds.

·        The length of time that a field is cultivated is usually shorter than the period over which the land is allowed to regenerate by lying fallow.

·        This technique is often used in LEDCs (Less Economically Developed Countries) or LICs (Low Income Countries).

·        In shifting agriculture, after two or three years of producing vegetable and grain crops on cleared land, the migrants abandon it for another plot.

Land is often cleared by slash-and-burn methods—trees, bushes and forests are cleared by slashing, and the remaining vegetation is burnt. The ashes add potash to the soil. Then the seeds are sown after the rains.

A

14.

The westerlies blow from the sub-tropical high pressure belt to the sub-polar low pressure belts.

They are called the westerlies as they blow constantly from the west.

In the Northern Hemisphere, they blow from the south-west to the north-east, and in the Southern Hemisphere they blow from the north-west to the south-east.

In Southern Hemisphere, there are no large land masses between 40° latitude and the 70° latitude to break the flow of the westerlies. Therefore the westerlies pick up great force and speed in these latitudes.

They blow with such force that they are known as the Roaring Forties in the 40° belt, the Furious Fifties in 50° belt and Screeching Sixties in 60° belt.

A   

15.

Wegener believed that there is three layers system within the earth, i.e. SIAL, SIMA and NIFE.  SIAL is lighter than the SIMA.   The continental masses are made of lighter materials (SIAL) and the oceans are made of denser material (SIMA). Thus, the continents are floating over the SIMA without any resistance offered by SIMA.  He assumed that all the landmasses were united together to form a one giant landmass, which he named Pangaea during Carboniferous period.  There were also some inland scattered over the Pangaea and was surrounded by a huge water body, which he named Panthalasa.

Here it must be mentioned that Wegener, considered that northern part of Pangaea as Lauratia and southern part of Pangaea as Gonwanaland.  Lauratia consists of present North America, Europe, and Asia. Whereas Gondwana consists of present South America, Africa, Madagascar, Peninsular India, Australia and Antarctica. Thus, Wegener’s theory of continental drifting begins from Carboniferous period. South pole was located near Durban. The Pangaea was disrupted during subsequent periods and broken landmasses drifted away from each other and thus the present position of the continents and ocean basins became possible.

Continental Drift Theory

·  Continental drift theory was proposed by Alfred Wegener in 1912.

·  It was first put forward by Abraham Ortelius in 1596 before fully being developed by Alfred Wegener.

·  The theory deals with the distribution of the oceans and the continents.

·  According to Wegener’s Continental Drift theory, all the continents were one single continental mass (called a Supercontinent) – Pangaea and a Mega Ocean surrounded this supercontinent. The mega ocean is known by the name Panthalassa.

·  Although Wegener’s initial theory did not cover mantle convection until Arthur Holmes later proposed the theory.

·  The supercontinent was named Pangaea (Pangea) and the Mega-ocean was called Panthalassa.

·  According to this theory, the supercontinent, Pangaea, began to split some two hundred million years back.

·  Pangaea first split into 2 big continental masses known as Gondwanaland and Laurasia forming the southern and northern modules respectively.

·  Later, Gondwanaland and Laurasia continued to break into several smaller continents that exist today.

Evidence supporting the Continental Drift Theory

1.      The Matching of Continents (Jig-Saw-Fit)

·  The coastlines of South America and Africa fronting each other have a remarkable and unique match.

·  In 1964, Bullard created a map using a computer program to find the right fit of the Atlantic margin and it proved to be quiet.

2.      Rocks of the Same Age across the Oceans

·  The radiometric dating methods have helped in correlating the formation of rocks present in different continents across the ocean.

·  The ancient rocks belts on the coast of Brazil match with those found in Western Africa.

·  The old marine deposits found on the coasts of South America and Africa belong to the Jurassic Age. This implies that the ocean never existed before that time.

3.      Tillite

·  It is the sedimentary rock made from glacier deposits.

·  The Gondwana system of sediments from India is recognized as having its counterparts in 6 different landmasses in the Southern Hemisphere.

·  Counterparts of this series are found in Madagascar, Africa, Antarctica, Falkland Island, and Australia not to mention India.

·  At the base, the system has thick tillite signifying widespread and sustained glaciation.

·  Generally, the similarity of the Gondwana-type sediments shows that these landmasses had exceptionally similar origins.

·  The glacial tillite gives clear evidence for palaeoclimates and the drifting of continents.

4.      Placer Deposits

·  The presence of abundant placer deposits of gold along the Ghana coast and the complete lack of its source rocks in the area is a phenomenal fact.

·  The gold-bearing veins are present in Brazil and it is evident that the gold deposits of Ghana in Africa are obtained from the Brazil plateau from the time when the two continents were beside each other.

·  The widespread distribution of Permo-Carboniferous glacial sediments in South America, Africa, Madagascar, Arabia, India, Antarctica, and Australia was one of the major pieces of evidence for the theory of continental drift.

·  The continuity of glaciers, inferred from oriented glacial striations and deposits called tillites, suggested the existence of the supercontinent of Gondwana, which became a central element of the concept of continental drift.

5.      Distribution of Fossils

·  The interpretations that Lemurs occur in India, Africa, and Madagascar led to the theory of a landmass named “Lemuria” connecting these 3 landmasses.

·  Mesosaurus was a tiny reptile adapted to shallow brackish water.

·  The skeletons of these creatures are found in the Traver formations of Brazil and the Southern Cape Province of South Africa.

Force for Drifting

·  Wegener proposed that the movement accountable for the drifting of the continents was instigated by tidal force and pole-fleeing force.

·  The polar-fleeing force relates to the rotation of the earth.

·  The shape of the earth

·  The second force that was proposed by Wegener, the tidal force.

·  However, most scholars considered these forces to be insufficient.

B   

16.

The Himalayan Mountains are the largest terrestrial mountain chain in the world. This mountain range formed at a convergent boundary between the Eurasian Plate and Indian Plate. These two plates are both continental plates.

Since the oceans are deep, a long column of water lies above the oceanic crust whereas the contintental crust is occupied by landmass for the same length of column. This explains that continental crust is thicker than the oceanic crust.

C 

17.

C

18.

Tides are single wave phenomenon which covers the entire ocean basin, where as sea waves are succession of waves approaching the sea shore one after another.

1.    Tides are shallow water waves but with very long wavelength even in the deep ocean basin.

2.    Tides are differentiated from wind driven sea waves with respect to wavelength mode of origin etc. Tides are originated due to interactions of the sun and the moon with ocean surfaces while sea waves are generated by wind drag. Sea waves are also originated by other factors such as atmosphere pressure, temperature variations salinity variations etc.

3.    Tides are low waves but with high energy while sea waves are high waves with low energy

4.    Sea waves such as rouge waves and storm breakers have very high crest but are localized phenomena but tides are widespread phenomenon they stretch across the entire ocean basin.

5.    The vertical difference between high tide water and low tide water is called the tidal wave height or tidal range which generally varies between less than 2 meters to more than 4 meters.

6.    The rise of seawater and its movement towards the coast is called tide and the resultant high water level is known as high tide water (H.T.W) while the fall of the seawater and its movement towards the sea is called ebb and the resultant low water level is known as low tide water (L.T.W)

7.    There is much variation in the height of high and low tides at different places in different oceans because of varying characteristics of the depth of ocean water, configuration of sea coasts and coastlines and openness or closeness of the seas.

8.    Gravitational pull of ocean water is called tidal bulge which occurs at two places. One bulge is towards the moon and the other is away from the moon on the opposite side of the earth, i.e. opposite to the first bulge. The tidal bulge which is created on the earth’s water surface by the gravitational force of the moon are called lunar tidal bulges. Thus each place on the earth experience bulges twice each day, i.e. they occur at the interval of 12 hours 25 minutes each day. The total period of two bulges each day is called lunar day.

9.         Like moon, sun also produces bulges on opposite sides of the earth by its gravitational force. The bulges created by the sun on the earth’s water surface are called solar bulges. One bulge is oriented towards the side of the sun while the other bulge is oriented towards the opposite side of the earth. The size of the solar bulge is 46 percent small than the lunar bulge because the gravitational pull of the moon far exceeds the gravitational pull of the sun.

The coastward transgression of seawater under the influence of tidal waves is called flood tide while seaward regression of water of tidal bulge is called ebb tide.

A 

19.

The compounds eat away at ozone, but only if light is present and the air is cold enough. This puts Polar Regions at particular risk when the sun returns after long dark winters.

Ozone depletion is primarily caused by man-made compounds that release chlorine and bromine gases in the stratosphere. Beginning in 1987, the internationally agreed-upon Montreal Protocol on Substances that Deplete the Ozone Layer has regulated these ozone-depleting compounds, such as chlorine-containing chlorofluorocarbons used in refrigerants and bromine-containing halon gases used as fire suppressants. Because of the Protocol, atmospheric levels of these ozone depleting compounds are slowly declining. The ozone hole is expected to recover back to 1980 levels in approximately 2070.

C

20.

D

21.

https://www.financialexpress.com/business/defence-securing-maritime-horizons-for-a-sustainable-future-uniting-31-nations-of-the-iora-and-dcocja-3241301/

B

22.

https://www.livescience.com/44292-international-date-line-explained.html

A   

23.

https://education.nationalgeographic.org/resource/ocean-trench/

·       Ocean trenches are formed by subduction between a plate carrying continental crust and a plate carrying oceanic crust.

·       Ocean trenches are a feature of convergent plate boundaries, where two or more tectonic plates meet.

·       At many convergent plate boundaries, dense lithosphere melts or slides beneath less-dense lithosphere in a process called subduction, creating a trench.

·       A subduction zone is a collision between two of Earth''s tectonic plates, where one plate sinks into the mantle underneath the other plate.

·       A transform fault or transform boundary, is a fault along a plate boundary where the motion is predominantly horizontal.

·       Normal faults are inclined fractures where the blocks have mostly shifted vertically.

·       The World''s deepest oceanic trench is Mariana.

·       The Mariana Trench is located in the western Pacific Ocean about 200 kilometers east of the Mariana Islands.

o It is the deepest oceanic trench on Earth.

o It is 1,580 miles long and averages just 43 miles wide.

o It is home to the Challenger Deep, which, at 10,911 meters (35,797 feet), is the deepest part of the ocean.

A 

24.

·       Nitrous oxide is emitted during agricultural, land use, and industrial activities; combustion of fossil fuels and solid waste; as well as during treatment of wastewater.

·       Nitrous oxide is generated during the nitrification-denitrification stage of biological wastewater treatment. During nitrification, ammonia oxidizes into nitrites and nitrates.

·       Nitrous oxide, also known as “laughing gas,” is the most important greenhouse gas after methane and carbon dioxide and the biggest human-related threat to the ozone layer.

·       https://www.epa.gov/ghgemissions/overview-greenhouse-gases#:~:text=Nitrous%20oxide%20molecules%20stay%20in,1%20pound%20of%20carbon%20dioxide.&text=Globally%2C%2040%25%20of%20total%20N,emissions%20come%20from%20human%20activities.

B 

25.

https://science.howstuffworks.com/science-vs-myth/what-if/what-if-earth-stopped-spinning.htm

If Earth did not rotate on its axis, one side would always face the Sun while the other side would be away from the Sun. Thus, one side would become very hot and the other side would become very cold. Ultimately, life would not have been possible under such circumstances. However, the formation of seasons and the occurrence of leap years take place due to the revolution of the Earth and not due to the rotation of the Earth.

A