Single slit experiment. A beam of light of wavelength 680 nm passes through a slit that is 1.9 µm wide. The distance between the slit and the screen is 3.0 m. How far, in centimeters (cm), away from the centerline does the first dark fringe occur?

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

Ibelieve the answer is either b or c, but i'm leaning more towards c.hope my answer has you : )