A$0\mathrm{.}50$kg object is attached to an ideal massless spring of spring constant $20$N$/$m along a horizontal, frictionless surface. The object oscillates in simple harmonic motion and has a speed of $1\mathrm{.}5$m$/$s at the equilibrium position.

$($a$)$ What is the amplitude of vibration?

$($b$)$ At what location are kinetic energy and the potential energy of the system the same?