First step is to compute for the interest that is gained from the described investment.
               I = P x i  x n
where P is the principal amount, i is the interest rate, and n is the number of years.
               I  = ($1200) x 0.04 x 8 = $384
Then, we add the interest gained to the original amount.Â
            F = P + I = ($1200) + ($384) = $1584
Thus, the amount after 8 years is $1584.Â