List of top Environmental Studies Questions on Composition and Structure of the Atmosphere

Match List I with List II

LIST I		LIST II
A	Troposphere	I	Ozone depletion
B	Basel convention	II	Aurora
C	Montreal protocol	III	Global warming
D	Bamako convention	IV	Artificial satellites

Choose the correct answer from the options given below:

Which of the following is the most dominant gas in the earth's atmosphere?

The main constituents of Acid rain are

Reason for acid rain is the pressure of the following gas in the atmosphere.

Given below are two statements: One is lebelled as Assertion A and the other is labelled as Reason R.
Assertion A: The average composition of atmosphere near the surface of the earth is approximately 78.08% of N₂, 20.95% of O₂, 0.93% of Ar, 0.04% of CO₂, adds to nearly 100%. 
Reason R: Water content in atmosphere is variable ranging from <0.5% to 3.5% therefore, the average composition is given on dry weight percent basis (mixing ratio).
In the light of the above statements, choose the correct answer from the options given below:

Which layer of the atmosphere reflects back the radio waves that are transmitted from the earth ?