Energy- physics question. Right answer will get best answer a.s.a.p

If anyone can help me with some of these q's :)

The winning time for the 2005 annual race up 86 floors of the Empire State Building was 10min and 49s . The winner's mass was 60kg .

A.
If each floor was 3.7 m high, what was the winner's change in gravitational potential energy?
Express your answer using two significant figures in kJ.

B.
If the efficiency in climbing stairs is 25% , what total energy did the winner expend during the race?
Express your answer using two significant figures in kJ.

C.
How many food Calories did the winner "burn" during the race?
Express your answer using two significant figures in Cal.

D.
Of those Calories, how many were converted to thermal energy?
Express your answer using two significant figures in Cal.

E.
What was the winner's metabolic power in watts during the race up the stairs?
Express your answer using two significant figures in Watts.

A) = 3.7*86=318.2m
PEg=hmg=318.2*60*9.81
=187292.52J = 190KJ

B) 25% efficiency, Therefore, real energy consumed is 4 times what is required.
4*187292.52J = 750KJ

C) 4.184 jouls in a calorie
749170/4.184 = 180,000Cal

D) Assume 75% energy lost goes to heat. multiply by 0.75
0.75*179055Cal = 130,000Cal

E) Watt = J/s, 10min 49s goes to 649secs. Use jouls from part B
749170/649 = 1200Watt

Enjoy