Niobium forms a substitutional solid solution with vanadium. Compute the number of niobium atoms per cubic centimeter for a niobium-vanadium alloy that contains 27 wt% Nb and 73 wt% V. The densities of pure niobium and vanadium are 8.57 and 6.10 g/cm3, respectively. Also, the atomic weights for niobium and vanadium are 92.91 and 50.94 g/mol, respectively.