4576: Due to improper/indiscriminate disposal of old and used computers or their parts, which of the following are released into the environment as e-waste?
1. Beryllium
2. Cadmium
3. Chromium
4. Heptachlor
5. Mercury
6. Lead
7. Plutonium
Select the correct answer using codes given below.
(a) 1, 2, 3, 5 and 6 only
(b) 2, 4, 5 and 7 only
(c) 1, 3, 4, 6 and 7 only
(d) 1, 2, 3, 4, 5, 6 and 7
4577: Which one of the following cities is nearest to the equator ?
(a) Jakarta
(b) Colombo
(c) Singapore
(d) Manila
4578: "Black holes" refers to
(a) Holes occurring in heavenly bodies
(b) Bright spots on the sun
(c) Collapsing object of high density
(d) Collapsing object of low density
4579: The sportsperson Soma Biswas is associated with
(a) Sailing
(b) Hockey
(c) Golf
(d) Athletics
4580: Assertion (A):
During the time of Akbar, for every ten cavalrymen, the mansabdars had to maintain twenty horses.
Reason (R):
Horses had to be rested while on march and replacements were necessary in times of war.
(a) Both A and R are true, and R is the correct explanation of A
(b) Both A and R are true, but R is not a correct explanation of A
(c) A is true, but R is false
(d) A is false, but R is true