The energy thats given to the body by food is

The body gets its energy from the food we eat. This food is converted to energy which is measured in calories. One calorie is the amount of energy needed to raise one gram of water by one degree Celsius. When we eat food, we give the body fuel to convert into energy, which our bodies then use for doing anything from breathing to running.

This is true. yes. indeed.

The answer would be age 18.