2t35-1-2 The graph above shows the position of a mass attached to an ideal spring as a function of time in a damped medium. The vertical scale is in meters

and the horizontal scale in seconds. It is known that the phase constant is do= -0.77 rad. (a) What is the period in seconds? (b) What is the damping constant b/2m of the motion, in s^-1? (c) What is the natural frequency of vibration of the spring-mass system, in rad/s? (d) How much percentage mechanical energy is lost in one cycle?