Kinetic Energy and the Power of Human Climbing

[jolly_20]

How to calculate the height of a person climbs from the third stair up? i don'[y know how to calculate it. HELP!

I have the mass=68kg, individual step height=0.16m, number of steps in flight=12

additional question: calculate the average power each person exerted while climbed the stairs.
i have the time= 2.9s for its average seconds.. Help!

 

[jolly_20]

Conservation of energy

In carrying out this investigation, what assumption do you make about each climber's kinetic energy?(the investigation being someone climbing a set of stairs, timing it and measuring the height) HELP!