A 2-kg mass is attached to a spring with a spring constant of 40 N/m. The medium offers a damping force that is numerically equal to 8 5 times the instantaneous velocity. If the mass is initially released from 10 cm below the equilibrium position at initial downward velocity of 2 m/sec, find the equation of motion. Also determine if the system is underdamped, critically damped, or overdamped