An Ambulance Is Generating a Siren Sound at a Frequency $2,400 \mathrm{~Hz}$

An ambulance is generating a siren sound at a frequency of $2,400 \mathrm{~Hz}$ . The speed of sound is $345.0 \mathrm{~m} / \mathrm{s}$ . The observer is traveling at a velocity of $24.00 \mathrm{~m} / \mathrm{s}$ toward the ambulance and the ambulance is traveling at a velocity of $24.00 \mathrm{~m} / \mathrm{s}$ away the observer. What is the frequency of the siren perceived by the observer?

A) $2,424 \mathrm{~Hz}$
B) $2,352 \mathrm{~Hz}$
C) $2,376 \mathrm{~Hz}$
D) $2,448 \mathrm{~Hz}$
E) $2,400 \mathrm{~Hz}$