You bring a boat toward the dock by pulling on a rope with a force of 150 newtons through a distance of 7 meters. (a) How much work do you do? (Include the appropriate sign.) (b) Then you slow the boat down by pushing against it with a force of 40 newtons, opposite to the boat's movement of 2 meters. How much work do you do? (Include the appropriate sign.) (c) What is the total amount of work that you do?