a) the amount of energy released by burning 1 lb offat is 1 lb (453.8 g / 1lb)(9 K cal / 1g)(4186J/1Kcal)= 1.71\times 107J mechanical energy out put is 1.71\times 107J (0.20) = n mg (no .of steps)height cos 0o 1.71\times 107J (0.20) = n (57.0 kg)(9.8 mis2)(90) (0.150 m )number of times she must climb the steps is n = [1.71\times 107J (0.20)] /(57.0 kg)( 9.8 mis2)(90 )(0.150m) simplify the above youwill get the answer

b) power output P = W/t = [ (57.0 kg)( 9.8 mis2)(90 )(0.150m)]/ 67.0 s simplify for the answer 1 h p = 746 W

b) power output P = W/t = [ (57.0 kg)( 9.8 mis2)(90 )(0.150m)]/ 67.0 s simplify for the answer 1 h p = 746 W