The equation for annual interest is A = P(1 + r)^t. We can plug in the known information and get A = 16,000(1 + (0.06))^3.5. Next, we can simplify this equation to A = 16,000(1.06)^3.5. Finally, we raise 1.06 to the power of 3.5 and multiply that by 16,000 and get an answer of $19,619.62.
Hope this helps!