I know this is late, but I can help explain so you can understand it.
Use this: A = P(1 + r)t
So,
P = 2,000 (How much you starting off)
r = 3.5% or 0.035 (your interest)
t = 3 (years)
The formula looks like this: 2000(1 + 0.035)^3
2000(1.035)^3
2000 x 1.1087...
= 2217.44
