There are five classes of food, out of this five only two provides energy; these are carbohydrate and fat and oil. Out of these two, carbohydrate provides the most energy for the body in the shortest time. This is the reason why glucose, which is the end product of carbohydrate is normally given to sport men during games.
c because the elasticity of arteries allow them to expand and contain more blood in them.
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Growth, repair, reproduce