A mass attached to a vertical spring has position function given by $s(t) = 2 \sin ( 4 t + 1.2) + 4$ where $t$ is measured in seconds and $s$ in inches. This is an example of simple harmonic motion.
Find the velocity at time $t$.
$v(t) =$ inches per second.
Find the acceleration at time $t$.
$a(t) =$ inches per second per second.