In this food chain energy moves from one living thing to another. What source of energy starts this food chain? A)
grass
B)
the Sun
C)
the air
D)
mushroom

B. The Sun

Explanation:

This is because almost everything needs sun to live. It is a continuous cycle. If there is no sun for a long period of time, most things will die, or start to wilt if it is a plant like grass.

i believe it is "they are not used up by reactions" as the answer to your question, text me back if this is correct because i just learned this.

the energy generated by an individual's metabolism is calculated in met (metabolic equivalent of task). the met is the ratio of the work metabolic rate to the resting metabolic rate. one met is illustrated as 1 kcal per kilogram per hour, and is probably equal to the energy cost of sitting quietly.

1 met is equal to 1.162 watt per kg

1 kg is equal to 1000 grams

as the person weighs 80000 gm, that is, 80 kg.

therefore, 80*1.162 = 92.96

thus, the person expends 92.96 watts of power while at rest.