Answer
Will.
Work Step by Step
The amount A after t years due to a principal P
invested at an annual interest rate r, expressed as a decimal,
compounded n times per year is $A=P\displaystyle \cdot(1+\frac{r}{n})^{nt}$
If compounding is continuous, $A=Pe^{rt}$
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Will:
$A=2000\displaystyle \left(1+\frac{0.09}{2}\right)^{(2)(20)}={{\$}} 11,632.73$
Henry:
$A=2000e^{(0.085)(20)}={{\$}} 10,947.89$
After 20 years, Will has more than Henry.
