The change in energy consumption in the united states durning the past 100 years is due to

a. by using fur or clothes to trap heat energy near the body

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.

(nitrogen fixation) will be your answer sorry if im wrong