Sun warms the earth with Electromagnetic Radiations.
Sun emits out short range radiation in the form of Electromagnetic (EM) Radiation. Our Atmosphere is transparent to EM radiation. It does not heats up the atmosphere but when it collide with the solid objects or particles it is absorbed, reflected or refracted and the object heats up and start emitting radiation in the form of long wave radiation. Our Earth does the same. The long wave radiation emitted by the earth surface is absorbed by our atmosphere and it heats up. Therefore, we can say our atmosphere is heated from below.
Water breaks down into hydrogen and oxygen: It is a decomposition reaction as a single substance decomposes to give two products.

Leaves make starch using chlorophyll and carbon dioxide: Synthesis reaction: as the synthesis reaction involves two or more than two reactants which join together to result into a single main product along with the formation of simple by products.

Food burns in oxygen gas and releases a lot of energy: Combustion: Combustion process involves the use of oxygen to give products along with release of energy.

Adding vinegar (acid) to baking soda (alkali) gives a product that is neither acidic nor alkaline: Neutralization: acetic acid in vinegar reacts with soda (base) to give salt (neutral) and .

<span>Nonliving things also have unlimited duration of existence. While living things die and decompose, nonliving things such as rocks, mountains, air and water have existed for millions of years. They may grow, but they do so only by accretion, which is the process of growth by accumulating added layers of matter.</span>
The answer to question one is A.
The answer to question two is A.
The answer to question three is D.