Answer: C

Explanation:

The red-headed vulture is also known as the Asian king vulture, Indian black vulture or Pondicherry vulture. It is an Old World vulture found primarily in the Indian subcontinent, with small populations found in parts of south-east Asia. The flying squirrel is one of more than 50 species of gliding squirrel. Three species are North American, two are found in northern Eurasia, and all the others are found in temperate and tropical forests of India and other parts of Asia. Gee Golden Langur (Trachypithecus geei) also known as Golden Langur. It is an ancient ape of the world which is found in a small area of western Assam and the foothills of the Black Mountains of Bhutan. Koala is a herbivorous marsupial native to Australia.  Hence, option (c) is correct.

Answer: A

Explanation:

Industrialized countries banned the use of CFCs in 2000 and the use of HCFCs will be banned by 2020. Alternatives to hydrochlorofluorocarbons (HCFCs) are expensive products, such as hydrofluorocarbons (HFCs) called third-generation refrigerants. The plan is that developed countries will start phasing out the use of HCFCs in 2013 and will completely phase them out by 2030. HFCs are already being used in developed countries because HFCs do not contain chlorine. Therefore, they do not cause any harm to the ozone layer. But HFCs are supergreenhouse gases that have the potential to cause additional global warming. This means that they can absorb large amounts of infrared radiation in the atmosphere and produce a greenhouse effect a thousand times greater than carbon dioxide. Hence, option (a) is correct.

Answer: D

Explanation:

Eucalyptus plantations of gangetic plains - Due to high income, Eucalyptus is called the tree of farmers in Punjab and the area of its plantation in 1984-85 was about 7,12,000 hectares. Farmers can grow wheat, berseem, moong, sugarcane and potato crops between plants planted at a distance of 3.5-6 metres. Good yield is obtained by intercropping. The average annual increase in this is about 20 m³. Hence, option (d) is the correct answer.

Answer: C

Explanation:

An ecotone is a transition zone between two or more diverse ecosystems. For example, mangrove forests represent an ecotone between marine and terrestrial ecosystems. Other examples are grasslands, estuaries and river banks. Hence, statement 1 is correct.

A well-developed ecotone contains few organisms that are completely isolated from surrounding communities. Sometimes the number of species and the population density of some species is much higher than that of any other community in the region. Hence statement 2 is correct.

Sometimes the number of species and the population density of some species is much higher than that of any other community in the region. This is called edge effect. The organisms found primarily or in greatest abundance in this region are known as edge species. The edge effect particularly applies to birds in terrestrial ecosystems. For example, the density of birds is higher in the mixed habitat of the ecotone between forest and desert. Hence, statement 3 is correct.

Answer: A

Explanation:

During peak traffic hours, automated vehicles of all types emit large amounts of carbon monoxide, hydrocarbons and nitrogen oxides. Two-wheelers and three-wheelers contribute 60% of total CO and 83% of total hydrocarbons, while heavy traffic vehicles contribute 55 to 80% of oxides of nitrogen. It is estimated that a car (without cleaning device) emits 350 kg CO, 0.6 kg SO 2 , 0.1 kg lead and 1.5 kg suspended particulate matter for every 1000 liters of fuel used. Hence, option (a) is correct.