(a) What is termed as 'breath of life' ?
(b) What is atmosphere ? List its four main concentric layers.
( c) Give three important aspects of atmospere.

Explanation

(a) Air is called 'breath of lige'.
(b) The envelope of air that suppounds our planet earth is called atmosphere. The four main cocentric layers of atmophere are troposphere, stratosphere, mesosphere and thermosphere.
( c) Atmosphere serves as
(i) protective blanket filtering harmful UV radiations from the sunlight that fall on the earth.
(ii) a place for many climatic events such as convection currents (winds), clouds formation, lightening thundering, precipitation etc.
(iii) reservoir of important elements which are essential for the life.