Answer:
F = 145 N
Explanation:
Given that,
Force applied by Jeff is 85 N and the force applied by Chris is 60 N. Both forces are acting in the same direction to push a rock up a hill. It means that net force is equal to the sum of these two forces.
So,
Net force on the rock = 85 N + 60 N
= 145 N
Hence, the net force on the rock is 145 N.