$12$ months

$($a$)$ A loan is made for five years at a simple interest rate of $12\%$ per annum. What is the equivalent annual effective rate of discount during the fourth year of the loan?

$($b$)$ Consider an account governed by simple interest at the simple interest rate $s.$ The effective rate of interest in the fifth year is given to be $0\mathrm{.}045.$ Find $s.$