Explanation:
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<span>Earth (and hence the observer) moves.</span>
Answer:
A. False, frequency can increase or decrease wavelength.
For example: a high frequency would mean there are shorter wavelengths that occur in a period. Meanwhile, a low frequency would indicate that the wavelengths are longer and in longer periods.
48 meters.
12 m/s and 4 seconds, so 4*12=48.