$($i$)$ Lewis needed a holiday and borrowed $$6500$ to fund it$.$ It was agreed that simple

interest would be charged at $6\mathrm{.}4\%$ pa$.$ and that he would pay off the loan in $3\mathrm{.}5$ years.

What was the total interest paid by Lewis on the loan?$($ii$)$ Super Bank pays $2\mathrm{.}44\%$ per annum compounded quarterly on its best deposit

account while Great Credit Union pays $2\mathrm{.}46\%$ per annum compounded semi$-$annually.

Show calculations and use the effective interest rate formula to find which investment

opportunity is the best alternative for a prospective saver.