Harmful ultraviolet radiations from the sun causes:

The upper stratosphere consists of considerable amount of X. X protects us from the harmful ultraviolet radiations coming from the sun. These radiations cause skin cancer (melanoma) in humans. X is :

The upper stratosphere consists of considerable amount of X. X protects us from the harmful ultraviolet radiations coming from the sun. These radiations cause skin cancer (melanoma) in humans. X is :

A considerable part of the harmful ultraviolet radiation of the sun does not reach the surface of earth. This is because in the upper atmosphere, there is a layer of

A considerable part of the harmful ultraviolet radiation of the sun does not reach the surface of earth. This is because in the upper atmosphere, there is a layer of

A considerable part of the harmful ultraviolet radiation of the sun does not reach the surface of earth. This is because in the upper atmosphere, there is a layer of