Consider the following statements:1. Nearly 99 percent of the total mass of the atmosphere lies within 30 km of the Earth's surface.2. The proportion of ozone in the atmosphere increases to a maximum at about 60 km from Earth's surface.Which of the statements given above is/are correct?

Consider the following statements:1. Nearly 99 percent of the total ma

1.	Consider the following statements:1. Nearly 99 percent of the total mass of the atmosphere lies within 30 km of the Earth's surface.2. The proportion of ozone in the atmosphere increases to a maximum at about 60 km from Earth's surface.Which of the statements given above is/are correct?
A.	only
B.	only
C.	oth 1 and 2
D.	either 1 nor 2
Answer» B. only