I need help with my physics hw. I already attempted it, but I don't understand what I'm meant to do.?

power P = 70*80*9.806/(0.1*60*11) = 830 watt (quite a number, being more than 1HP) ) 

There are FOUR things being tested.  1 Do you recognize that in SI you must use seconds for time.?  2.  Do you know that power = energy / time?  3.  Do you recognize that gravitational energy = mgh. 4. IF 10 % goes into gravity how do you find 100% when you know 10%?

OK so metabolic energy =mgh *100/10

Power = metabolic energy / time = mgh * 100/10 / (11*60) = 80*9.8*70 *10/(11*60) ~=830W  Which is a very realistic figure.

Gravitational energy change = mgh = (80 kg)(9.8 m/s²)(70 m) = 54880 J

If gravitational energy change of 54880 J is 10%, then total energy expended will be...

Total energy = (100%/10%)*54880 J = 548800 J

Average metabolic rate = Total energy/time in sec = (548800 J)/[(11min * 60)s] ≈ 832 W

energy to climb 70 m, E = mgh = 80•9.8•70 = 54880 J

total energy expended would be 10 times that or 548800 J

power in watts = energy in joules / time in seconds

11 min = 660 s

P = 548800 J / 660 s = 832 J/s or 832 watts

What is the energy needed to move an 80 kg mass upwards by 70 m in the Earth's gravitational field.?

The question says that that amount of energy is only 10% of the climber's energy over an 11 minute period, so the total energy in 11 minutes is 10X as much.   The metabolic rate is the average energy expenditure per unit time.