Suppose you increase your walking speed from 4 m/s to 12 m/s in a period of 1 s. what is your acceleration?

Initial speed = 4 m/s
Final speed = 12 m/s

Acceleration = (final speed - initial speed) / (time for the change)

= (8 m/s) / (1 s)

=  8 m/s²

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