A 85 kg crate is lowered from a loading dock 3.4 m above the ground to the floor using a rope passing over fixed support

[answerhappygod]

A 85 kg crate is lowered from a loading dock 3.4 m above the
ground to the floor using a rope passing over fixed support.
Use down as a positive direction. The rope exerts a
constant upward force on the crate of 723 N. Let Fnet
be the net force acting on the mass, a = acceleration of the
system, t = time it takes to get to the floor, v = velocity as it
reaches the floor. Compute Fnet + 2*a +3*t +
4*v