Why are very high temperatures and pressures required for fusion to occur? to generate the neutrons that are needed to break the nuclei
to overcome the repulsion between the protons in the nuclei that join
to maintain the proper conditions to keep the chain reaction going
to keep the uranium fuel separate from the control rods

Hey hope you get the answer but i suck at math sorry : (

When is this

W= fd
where f is an applied force and d is the distance over which it is applied. when a parachuting skydiver is at constant velocity, he is experiencing "terminal velocity", the point at which his acceleration down is canceled out by air resistance. that means that the resisting force of the air is equal to his weight, but in the opposite direction. with this, we can solve for the work done by the force.
w = fd
w = (92.0)(9.81 m/s^2) (325)
w= 2.93 x 10^5 j
the value for work in this case is positive because it is pushing up on the skydiver, who has a downward force of gravity.
therefore the answer is 2.93 x 10^5 j