Answer:
Option C.
Explanation:
The equation that models the position of the weight and time will be a sine wave.
y = A sin(bt)
where A = amplitude of the wave
b = time period for a complete oscillation
Since b =
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It has been given in the question, Time period t = 3 sec.
b =

Amplitude A = 2 in.
Now we plug in the values of amplitude and time period in the standard equation.
y =

y =
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Option C. is the answer.