Considering a sinusoidal equation, and the concept of amplitude, if it found that the equation's amplitude is of 3 hours.
It is given by half the difference between the greatest and the smallest value.
In this problem:
0.5 x (15 - 9) = 3.
Hence, the equation's amplitude is of 3 hours.
More can be learned about sinusoidal equations at https://brainly.com/question/16818112
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