A standard work year is $2,400$ hours at the Luther Mill and it takes about $2$ hours to fill a customer order. Last year saw $18,000$ customer orders at the mill and the manager has a new Ford F$-150$ in mind as a company car, so he hopes that there is an increase of $10\%$ in customer orders for next year. If the manager hires $15$ workers, what is the capacity cushion?

A$)54\mathrm{.}2\%$

B$)8\mathrm{.}3\%$

C$)45\mathrm{.}8\%$

D$)91\mathrm{.}7\%$