Answer:
F = 4117.64
Step-by-step explanation:
First, we will calculate the acceleration of the hand, by using the third equation of motion:

where,
a = acceleration = ?
s = distance covered = compression = 8.5 cm = 0.085 m
vf = final speed = 0 m/s
vi = iniial speed = 10 m/s
Therefore,

negative sign hows deceleration.
Now, we will calculate the force exerted by the hand:

F = 4117.64 N