Now explore friction force. Set the piece of plastic or wood on the table and push it steadily across the tabletop using your fingertip. Note how much opposition to your push you feel. Repeat the steps, but this time push the piece of plastic or wood across a rug, carpet, or piece of fabric. If you’re using fabric, be sure to secure the fabric so it doesn’t move. How does the opposition to motion on the tabletop compare with that of the rug, carpet, or fabric?

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