As One Approaches a Certain Sound Source, the Sound Intensity $F ( x ) = - \frac { 2 ( x - 3 ) ^ { 2 } + 3 ( x - 3 ) - 9 } { 2 ( x - 3 ) + 30 }$

Multiple Choice

As one approaches a certain sound source, the sound intensity in arbitrary units increases according to the following function of time: $F ( x ) = - \frac { 2 ( x - 3 ) ^ { 2 } + 3 ( x - 3 ) - 9 } { 2 ( x - 3 ) + 30 }$ . Starting at $x = 0$ , when the source of sound is first sensed, how much time elapses until maximum sound intensity is felt? Round the result to the nearest hundredth.

A) 26.07 sec
B) 0.36 sec
C) 2.07 sec
D) 14.77 sec