Use Identities to Find the Exact Value $\frac { 5 } { \pi }$

Multiple Choice

Use Identities to find the exact value.
-A weight attached to a spring is pulled down 4 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) $\mathrm { s } ( \mathrm { t } ) = 4 \cos 10 \mathrm { t }$
B) $s ( t ) = 4 \cos 5 t$
C) $s ( t ) = - 4 \cos 10 t$
D) $s ( t ) = - 4 \cos 5 \mathrm { t }$