$11-20.$Assume that $3-$month Treasury bills totaling $$12$ billion were sold in $$10,000$ denominations at a discount rate of $3\mathrm{.}605\%.$ In addition, hte Treasury Department sold $6-$month bils totaling $$10$ billion at a discount rate of $3\mathrm{.}55\%.($a$)$ What si the discount amount for $3-$month bills? $($b$)$ What si the discount amount for $6-$month bills? $($c$)$ What si the effective rate for $3-$month bills? $($d$)$ What is hte effective rate for $6-$month bills? Round ot the nearest hun$-$