Which energy-level change shown in the diagram below emits electromagnetic radiation with the longest wavelength?

a) an electron moving from 4 to 5
b) an electron moving from 5 to 2
c) an electron moving from 6 to 1
d) an electron moving from 2 to 1

D.

Emission occurs when electrons move from a higher to a lower energy level and the energy of the emitted particle is inversely proportional to the wavelength. Thus, a high wave length means it was a small energy transition.

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