How many integer-valued solutions are there to each of the following equations and inequalities?a) x1 + x2 + x3 + x4 + x5 = 63, all xi > 0.b) x1 + x2 + x3 + x4 + x5 = 63, all xi ≥ 0.c) x1 + x2 + x3 + x4 + x5 ≤ 63, all xi ≥ 0.d) x1 + x2 + x3 + x4 + x5 = 63, all xi ≥ 0, x2 ≥ 10.e) x1 + x2 + x3 + x4 + x5 = 63, all xi ≥ 0, x2 ≤ 9.