Thinking about bonds and Treasury bills, which one of the following statements is correct?

Question $9$ Answer

a$.$

A Treasury bill that repays $100,000$ at the end of $91$ days is sold at a discount of $1525.$ The annual yield on this bill is $6\mathrm{.}21\%($to two decimal places$).$

b$.$

If the discount at which a Treasury bill is sold increases, the bill$$s yield falls.

c$.$

Ignoring any gain or loss when the bond is sold or redeemed, the yield on a bond with a nominal value of $100,$ a coupon of $2\mathrm{.}5\%$ and a market price of $97\mathrm{.}50$ is $2\mathrm{.}44\%($to two decimal places$).$

d$.$

A central bank can increase the yield on bonds by using a policy of quantitative easing.