4 - A microprocessor has two internal units, an instruction fetch unit and an instruction execute unit, with fetch/execute overlap. Compute the overall processing time of five sequential instructions, in each of the following cases: a) T(IF) = T(EX) = 100 ns for any instructions b) T(IF) = 100 ns (for any instruction), T(EX) = 50, 75, 125, 100, 75 for i = 1, 2, 3, 4, and 5 respectively.