Calvin buys equipment for his home office for $$15,600$ with a credit card. Which credit cardbelow would cost less to use, if neither card has an outstanding balance at the end of theyear? Assume Calvin can afford the monthly payment required. Explain. $(4$ marks$)$a$.$ Silver Card an interest rate of $18\mathrm{.}6\%,$ compounded daily, but gets $2\%$ cash back onpurchases at the end of the year.b$.$ Gold Card an interest rate of $17\mathrm{.}5\%,$ compounded daily, with no cash back.