A rectangular block of Styrofoam $25\mathrm{.}0$ cm in length, $15\mathrm{.}0$ cm in width, and $12\mathrm{.}0$ cm in height is placed in a large tub of water. Assume the density of Styrofoam is $3\mathrm{.}00102$ kg$/$m$3.$ a$.$ What volume of the block is submerged? b$.$ A copper block is now placed atop the Styrofoam block so that the top of the Styro$-$foam block is level with the surface of the water. What is the mass of the copper block?