Suppose you had a hollow tube, closed at both ends. The tube weighs 10 pounds and would float in water. Suppose also there is an empty container with a hole at the bottom. The tube is stuck through the hole so that half of it is in the tank and half is sticking out the bottom. Assume a water tight fit between the tube and the hole. Now, fill the tank with water so that the water surface is a foot or two above the top of the tube. How much force is necessary to pull the tube through the water and completely into the container? (Assume for the sake of argument that there is no friction between the tube and the sides of the hole). Is it (a) 10 pounds; (b) 10 pounds plus water pressure; (c) something less than 10 pounds because the top half of the tube is buoyant even though the bottom half is sticking out the bottom of the hole; or (c) something else?