The total number of years taken by Hank to recover the total investment he has done in his education is 6.6 years.
Computation of the number of years taken by Hank to recover investment is:
[tex]\begin{aligned}\text{Number of Years}&=\frac{ \text{Total Income per Year after degree}}{\text{cost of the education}} \\\text{Number of Years}&= \frac{\$33000}{\$5000}\\\text{Number of Years}&= 6.6\:Years\end{aligned}[/tex]
Therefore, the correct option is c.
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