Answer:
3.81 s
Explanation:
The object oscillates along a cosine wave:
x = A cos (2πt / T),
where A is the amplitude and T is the period.
Given that A = 14, and x = 6.70 when t = 0.65:
6.70 = 14 cos (2π (0.65) / T)
0.479 = cos (4.08 / T)
1.07 = 4.08 / T
T = 3.81
The period is 3.81 seconds.
