1601: There are 6 persons A, B, C, D, E and F. they are to be seated in a row such that B never sits anywhere ahead of A, and C never sits anywhere ahead of B. In how many different ways can this be done?
(A) 120
(B) 72
(C) 60
(D) None
1602: Which one of the following is the best description of the term 'ecosystem'?
(a) A community of organisms interacting with one another.
(b) That part of the Earth which is inhabited by living organisms.
(c) A community of organisms together with the environment in which they live
(d) The flora and fauna of a geographical area
1603: What is the new administrative capital proposed for Myanmar ?
(a) Pyinmana
(b) Myitkyina
(c) Mandalay
(d) Bassein
1604: Consider the following statements :
1. The duration of the monsoon decreases from southern India to northern India.
2. The amount of annual rainfall in the northern plains of India decreases from east to west.
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
1605: Why DDT is banned in western countries?
(a) It remains in environment for a long time
(b) The insects are immunised
(c) It is a highly poisonous insecticide
(d) None of the above