376: The minimum land area recommended for forest cover to maintain proper ecological balance in India is
(a) 25%
(b) 33%
(c) 43%
(d) 53%
377: In an objective test there are 60 questions. Each question carries four alternative answers only one of which is correct. Suppose A and B are two candidates both of whom know correct answers to 30 questions. A answers only 30 questions while B answers all 60 questions choosing answers at random for those he does not know the answers of. If each question carries a mark of 1 and no negative marks are awarded, the marks obtained by B are expected to be larger than those obtained by A by
(a) 0
(b) 15
(c) 5
(d) 7.5
378: A table has three drawers. It is known that one of the drawers contains two silver coins, another contains two gold coins and the third one contains a silver coin and a gold coin. One of the drawers is opened at random and a coin is drawn. It is found to be a silver coin. What is the probability that the other coin in the drawer is a gold coin ?
(a) 0.25
(b) 1.00
(c) 0.50
(d) 0.60
379: An athlete claimed that his timing for a 100 m dash should be corrected because the starting signal was given by a gun fired from a point 10 m away from him and the timekeeper was standing close to the gun. The error due to this could be (in seconds):
(a) 0.7
(b) 0.5
(c) 0.1
(d) 0.03
380: Regarding the atom of a chemical element, the magnetic quantum number refers to
(a) orientation
(b) shape
(c) size
(d) spin