Answer:
Part 1
C. Its frequency remains the same.
Part 2
A. A wave's frequency always remains the same.
Step-by-step explanation:
The relationship between wavelength, frequency, and speed is given as:
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When the frequency of a wave increases, its wavelength also increases.
The speed of a wave does not change as its frequency changes, and vice-versa.
Therefore, as the speed of the wave decreases, its frequency remains the same
A wave's frequency always remains the same regardless of the speed and wavelength