Which is not part of the recipe for a thunderstorm to form?

A. Moisture in the  law atmosphere

B. A cold front advancing 

C. A lifting force

D. Unstable air

1. Radiocarbon is produced in the atmosphere as a result of

A. collision between fast neutrons and nitrogen nuclei present in the atmosphere

B. action of ultraviolet light from the sun on atmospheric oxygen

C. action of solar radiations particularly cosmic rays on carbon dioxide present in the atmosphere

D. lightning discharge in atmosphere

What causes the development of most clouds and precipitation in the atmosphere?

1. Which is the main gas that makes up the Earth's atmosphere?