Solve the Problem $\frac { 1 } { 2 }$ Second, Determine a Trigonometric Model That Gives the Position of Pulled

Multiple Choice

Solve the problem.
-A weight attached to a spring is pulled down 7 inches below the equilibrium position. Assuming that the period of the system is $\frac { 1 } { 2 }$ second, determine a trigonometric model that gives the position of the weight at time $t$ seconds.

A) $y = 7 \cos \frac { 1 } { 2 } t$
B) $y = - 7 \cos 4 \pi t$
C) $y = 7 \cos 4 \pi t$
D) $y = - 7 \cos 2 \pi t$