811: Isotopes of the same element differ in the number of:
(a) Protons
(b) Neutrons
(c) Electrons
(d) Positrons
812: Assertion (A):
The thickness of the atmosphere is maximum over the Equator.
Reason (R):
High insolation and strong convection currents occur over the Equator.
(a) Both A and R are individually true and R is the correct explanation of A
(b) Both A and R are individually true but R is not the correct explanation of A
(c) A is true but R is false
(d) A is false but R is true
813: Consider the following statements:
As per 2001 Census
1. The two States with the lowest sex ratio are Haryana and Punjab.
2. The two States with the lowest population per sq km of area are Meghalaya and Mizoram.
3. Kerala has both the highest literacy rate and sex ratio.
Which of the statements given above is/are correct?
(a) 3 only
(b) 2 and 3
(c) 1 and 2
(d) 1 and 3
814: Which one of the following is also called Stranger Gas?
(a) Argon
(b) Nitrous oxide
(c) Xenon
(d) Neon
815: 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