Use excel and show your excel workbook with the formulas in each cell. A bond has just been issued. The bond will mature in $8$ years. The bond's annual coupon rate is $12\%$ and the face value of the bond is $$1,000.$ The bond's $($annual$)$ yield to maturity is $10\%.$

a$.$ Compute the bond's duration if coupons are paid quarterly:

i$.$ Using the VBA dduration function.