A weightlifter has a basal metabolic rate

Question

of 80.0 W. As he is working out, his metabolic rate
increases by about 650 W. (a) How many hours does
it take him to work off a 450-Calorie bagel if he stays
in bed all day? (b) How long does it take him if he’s
working out? (c) Calculate the amount of mechanical
work necessary to lift a 120-kg barbell 2.00 m. (d) He
drops the barbell to the floor and lifts it repeatedly.
How many times per minute must he repeat this process
to do an amount of mechanical work equivalent to
his metabolic rate increase of 650 W during exercise?
(e) Could he actually do repetitions at the rate found
in part (d) at the given metabolic level? Explain.