To answer this question, we have to compute the 5.1% of $66,770.
Recall that to compute the x% of y, we can use the following expression:
[tex]y\times\frac{x}{100}\text{.}[/tex]Substituting x=5.1, and y=66,770 in the above expression, we get:
[tex]66770\times\frac{5.1}{100}=3405.27.[/tex]Therefore, the commission will be $3405.27.
Answer: $3405.27.