3991: Which one of the following is an artificial lake ?
(a) Kodaikanal (Tamil Nadu)
(b) Kolleru (Andhra Pradesh)
(c) N ainital (Uttarakhand)
(d) Renuka (Himachal Pradesh)
3992: Which one of the following is the correct sequence of ecosystems in the order of decreasing productivity?
(a) Oceans, lakes, grasslands, mangroves
(b) Mangroves, oceans, grasslands, lakes
(c) Mangroves, grasslands, lakes, oceans
(d) Oceans, mangroves, lakes, grasslands
3993: The varieties of corn can be improved by which of the following methods?
(a) Dihybrid cross
(b) Back cross
(c) Double cross
(d) Natural selection
3994: By a regulation in 1793, the District Collector was deprived of his judicial powers and made the collecting agent only. What was the reason for such regulation?
(a) Lord Cornwallis felt that the District Collector's efficiency of revenue collection would enormously increase without the burden of other work
(b) Lord Cornwallis felt that Judicial power should compulsorily be in the hands of Europeans while Indians can be given the job of revenue collection in the districts
(c) Lord Cornwallis was alarmed at the extent of power concentrated in the District Collector and felt that such absolute power was undesirable in one person
(d) The judicial work demanded a deep knowledge of India and a good training in law and Lord Cornwallis felt that District Collector should be only a revenue collector
3995: A boy carved his initials on the-bark of a tree at a height of 2.5 m above the ground when the tree was 5 m tall. In 10 years the tree attained a height of 15 m. The initials carved by the boy 10 years ago will now be found:
(a) At 2.5 m above the ground
(b) At 7.5 m above the ground
(c) At 12.5 m above the ground
(d) At 15.0 m above the ground