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the distance, in inches, from the starting position of a swinging pendulum over time, in seconds, is represented by the graph below.

when f(x) = 0, the pendulum is at its starting position. when f(x) > 0, the pendulum is to the left of its starting position, and when f(x) < 0, the pendulum is to the right of its starting position.

the function describing this graph is a transformation of the parent cosine function, y = cos x.

which value best describes the amplitude of the transformed function?
a.
0 inches
b.
6 inches
c.
1.5 inches
d.
3 inches