A 4 ft spring measures 8 ft long after a mass weighing 8 pounds is attached to it. the medium through which the mass moves offers a damping force numerically equal to sqrt.2 times the instantaneous velocity. Find the equation of motion if the mass is initially released from the equilibrium position with a downward velocity of 5 ft/s. Find the time at which the mass attains its extreme displacement from the equilibrium postion. What is the position of the mass at this instant?