a) A block of iron is suspended from one end of an equal-arm balance by a thin wire. To balance the scales, 8.05 kg are needed on the scle pan at the other end. The density of iron is 7.87 *kg/m^3. The density of water is 9.98 *10^2 kg/m^3. What is the volume of the block (in m^3)?
b) Next, a beaker of water is placed so that the iron block is submerged in the beaker not touching the bottom. What mass (in kg) is now necessary to balance the scales?