C. The same ball rolls horizontally along the sand and decelerates at a rate of 6 m/s2. Calculate the force of friction that caused this deceleration.

Amass weighing 24 pounds, attached to the end of a spring, stretches it 4 inches. initially, the mass is released from rest from a point 8 inches below the equilibrium position. find the equation of motion. (use g = 32 ft/s2 for the acceleration due to gravity.)