A block of wood has a mass of 3.72 kg and a density of 601 kg/m3. It is to be loaded with lead (1.13 x 104 kg/m3) so that it will float in water with 0.891 of its volume submerged. What mass of lead is needed if the lead is attached to (a) the top of the wood and (b) the bottom of the wood? (a) Number i Units (b) Number Units