Answer the Question $s = S \sqrt { \frac { l } { L } }$

Multiple Choice

Answer the question.
-Police use a formula $s = S \sqrt { \frac { l } { L } }$ , where $S$ is the test-car speed and $L$ is the test-skid length, to find the actual speed $s$ in an accident which left a skid mark of l. Find the speed (nearest whole mph) when $S = 54 \mathrm { mph }$ , $l = 150 \mathrm { ft } , \mathrm { L } = 100 \mathrm { ft }$ .

A) $66 \mathrm { mph }$
B) $44 \mathrm { mph }$
C) $81 \mathrm { mph }$
D) $104 \mathrm { mph }$