How can I solve this? Please Help!

Question

Suppose your mass is 73.0 kg and you climb 40 stairs of height 18 cm in 18.0 s. What is your power output as you climb the stairs?

 _____ W

Answer 1

Power = Force * displacement/time

Force = mass * gravity

Power = mass * gravity * displacement/time

m = 73 kg

g = 9.81 m/s²

d = (0.18 m * 40) = 7.2 m

t = 18 s

P = (73 * 9.81 * 7.2)/18

P = 286.45 W