1616: Match List I (Oxdiation number) with List II (The element) and select the correct answer using the codes given below this lists:
List I List II
(Oxidation number) (The element)
A. 2 1. Oxidation number of Mn in MnO2
B. 3 2. Oxidation number of S in H2S2O7
C. 4 3. Oxidation number of Ca in CaO2
D. 6 4. Oxidation number of Al in NaAIH4
Codes:
A B C D
(a) 3 4 1 2
(b) 4 3 1 2
(c) 3 4 2 1
(d) 4 3 2 1
1617: The escape velocity from the earth's surface is about:
(a) 30 km/sec
(b) 6 km/sec
(c) 11.2 km/sec
(d) 300 km/sec
1618: In a question of a test paper, there are five items each under List-A and List-B. The examinees are required to match each item under List-A with its corresponding correct item under List-B. Further, it is given that:
(i) no examinee has given the correct answer
(ii) answers of no two examinees are identical
What is the maximum number of examinees who took this test?
(a) 24
(b) 26
(c) 119
(d) 129
1619: Amnesty International is
(a) an agency of the United Nations to help refugees of civil wars
(b) a global Human Rights Movement
(c) a non-governmental organization to help people voluntary very poor people
(d) an inter-governmental agency to cater to medical emergencies in war-ravaged regions
1620: Within biological communities, some species are important in determining the ability of a large number of other species to persist in the community. Such species are called
(a) Keystone species
(b) Allopatric species
(c) Sympatric species
(d) Threatened species