Assume that a machine includes a floating point unit, which contains an FP square root (FPSQR) instruction. Suppose we have the following measurements

Frequency of FP operations =30%,Frequency of FPSQR =4%

Average CPI of FP operations =4.0, CPI of FPSQR=20

Average CPI of other instructions(no-FP instructions)

a. What is the average CPI of the machine?

b.If the average CPI of FP is decreased to 3, what is the average CPI of the new machine?

c.If the CPI of FPSQR is decreased to 2, what is the average CPI of the new machine?

d.Which design improvement is better of b and c?

N.B: I need the solution with explanation