Problem $5\mathrm{.}12($Effective Rate of Interest$)$

Find the interest rates eamed on each of the following. Round your answers to the nearest whole number.

a$.$ You borrow $$650$ and promise to pay back $$767$ at the end of $1$ year.

$\%$

b$.$ You lend $$650,$ and the borrower promises to pay you $$767$ at the end of $1$ year.

$\%$

c$.$ You borrow $$64,000$ and promise to pay back $$104,250$ at the end of $10$ years.

$\%$

d$.$ You borrow $$18,000$ and promise to make payments of $$4,390,00$ at the end of each year for $5$ years.

$\%$