Build a spreadsheet that will calculate PV$,$ FV$,$ N$,$ PMT$,$ or r given the other $4$ inputs. The goal is to create something that can be copied to solve the questions below. You will use the following built in functions, PV$,$ FV$,$ PMT$,$ NPER, and RATE.

$1.$ A rich aunt promises you $$85,000$ exactly $4$ years after you finish your MBA.

$($a$)$ Given an interest rate of $5\%/$year$,$ what is that amount worth now, if you were to graduate today?

$($b$)$ What is it worth today if you were to instead receive that same amount in $8$ years?

$($c$)$ In each case, what if the relevant interest rate was $7\%$ per year?