An object is anached to a colled spring. It is pulled down a distance of $5$ units from its equilibrium position, and then reteased. The time for one complete oscillation is $3$ seconds

a$.$ Give an equation that models the position of the object at time $t$

$s(t)=$

$$

$($Simplify your arswer. Type an exact answer, using x as needed. Use inflegers or fractions for any numbers in the expresson$)$