Two Speakers in an Automobile Emit Sound Waves That Are

Multiple Choice

Two speakers in an automobile emit sound waves that are in phase at the speakers. One speaker is 40 cm ahead of and 30 cm to the left of the driver's left ear. The other speaker is 50 cm ahead of and 120 cm to the right of the driver's right ear. Which of the following wavelengths is(are) in phase at the left ear for the speaker on the left and the right ear for the speaker on the right?

A) 10 cm
B) 20 cm
C) 650 cm
D) All of the wavelengths listed above.
E) Only the wavelengths listed in (a) and (b) .