Determine the Equation of the Graph $\frac { 5 } { \pi }$

Multiple Choice

Determine the equation of the graph.
-A weight attached to a spring is pulled down 8 inches below the equilibrium position. Assuming that the frequency of the system is $\frac { 5 } { \pi }$ cycles per second, determine a trigonometric model that gives the position of the weight at time $t$ seconds.

A) $s ( t ) = 8 \cos 10 t$
B) $s ( t ) = - 8 \cos 5 t$
C) $s ( t ) = 8 \cos 5 t$
D) $s ( t ) = - 8 \cos 10 t$