Part (a)
I'll assume the interest compounds annually.
A = P*(1+r/n)^(n*t)
A = 15000*(1+0.04/1)^(1*2)
A = 16,224
Answer: $16,224
====================================================
Part (b)
Subtract the result of part (a) and the original deposit amount to find the interest earned.
interest = A - P = 16,224 - 15,000 = 1,224
Answer: $1,224
