The silver medal awarded to the second place winner in 2002 Salt Lake City Winter Olympics had a composition of 92.5 at% silver and 7.5 at% copper. Determine the absolute mass of each metal in a 253- gram medal. (a) Estimate the density of an 80 wt% Cu - 20 wt% Ni alloy, (b) What will be the most probable crystal structure for this alloy? (c) Determine the mass in grams of the atoms inside a unit cell of this alloy, (d) Determine the lattice constant for this alloy.