Consider the following two portfolios associated with the yield curve strategy: bullet portfolio: $100\%$ bond $C$ and Barbell portfolio: $50\%$ bond A and $50\%$ bond $B.$ Answer the following questions.

$\backslash$table$[[$Bond$,$Coupon Rate $(\%),$Price,$\backslash$table$[[$Yield to$],[$maturity$]],$Duration,Convexity$],[$A$,8\mathrm{.}50,100,4\mathrm{.}50,4,20],[$B$,9\mathrm{.}50,100,5\mathrm{.}50,8,120],[$C$,9\mathrm{.}25,100,5\mathrm{.}25,6,60]]$

Calculate yields, dollar durations, and dollar convexity for the two portfolios.

Which portfolio is more expensive to construct? Explain the concept of "the cost of convexity".

Assume you expect the yield curve won't change much in the following year. Which strategy among barbell and bullet would you pick?