The internal rate of return method is used by LeachObj. $3$Construction Co$.$ inanalyzing a capital expenditure proposal that involves an investment of $$400,125$ and annual net cash flow of $$75,000$ for each of the $8$ years of its useful life.a$.$ Determine a present value factor for an annuity of $$1$ which can be used in determining the internal rate ofreturn.Answerb. Using the factor determined in part$($a$)$ and the present value of an annuity of $$1$ table appearing in Exhibit $5,$ determine the internal rate of return for the proposal. SHOW ALL YOUR WORK!!