Hey, TheXSquaredFactor! I did the work with the frist one and I got the right answer so now I understand. Then I did the same method with the next one and this what I got:
A(r,t) = 100(1+r)^t
A(0.17,4) = 100(1+0.17)^4
A(0.17,4) = $187.388721
I suppose that this is right, but I don't know if I have to round the answer.