A metal block 2 ft square and 10 in. deep is floated on a body of liquid which consists of an 8-in layer of water above a layer of mercury. The block weighs 120 lb/ft3. What is the position of the bottom of the block? If a downward vertical force of 500 lb is applied to the center of this block, what is the new position of the bottom of the block ? Assume that the tank containing the fluid is of infinite dimensions.