Solve the following problems:
Problem I: A 81-kg man steps out a window and falls (from rest) 1.2 m to a sidewalk. What is his speed just before his feet strike the pavement?
m/s
Problem II: If the man falls with his knees and ankles locked, the only cushion for his fall is an approximately 0.53-cm give in the pads of his feet. Calculate the average force exerted on him by the ground during this 0.53 cm of travel. This average force is sufficient to cause damage to cartilage in the joints or to break bones.
N
Please show how you obtained the answer.