Consider two bonds A and B with payments $,$ where $.$ Bond A has just been issued. Its face value is $$1,000,$ it bears coupon rate of $7\%,$ and it will mature in $10$ years. Bond B was issued $5$ years ago. This bond has $$1,000$ face value and bears a $13\%$ coupon rate. When issued, this bond had a $15-$year maturity, so its remaining maturity is $10$ years. The yield to maturity for both bonds is $8\%($see Cell B$2$ in the spreadsheet below$).$ Using the Excel spreadsheet below write and explain the Excel formula used to calculate bond A and bond B prices in Cells B$17$ and E$17,$ respectively: