Suppose a 15-Centimeter Pendulum Moves According to the Equation $\theta = 0.6 \cos 8 t$

Multiple Choice

Suppose a 15-centimeter pendulum moves according to the equation $\theta = 0.6 \cos 8 t$ where $\theta$ is the angular displacement from the vertical in radians and $t$ is the time in seconds. Determine the rate of change of $\theta$ when $t = 7$ seconds. Round your answer to four decimal places.

A) $2.5034$ radians per second
B) $3.6185$ radians per second
C) $0.3129$ radians per second
D) $3.1535$ radians per second
E) $4.1724$ radians per second