Show how to solve in Excel: Suppose you own $$100$ par of a $20-$year bond that pays annually a coupon of

$4\%.$ The market interest rate, $R,$ is $5\mathrm{.}0\%$

a$)$ Calculate the PV$,$ Macauley Duration and Modified Duration $(9$ points$)$

b$)$ Suppose the market interest rate decreases by $1\%.$ Calculate $\frac{P}{P}$ and $P(8$ points$)$

Note: you must build a table and not use Excel bond or interest rate functions.