(6) a mass weighing 16 pounds stretches a spring 2 feet. att=0 the mass is released at a equilibrium position with a downward velocity 10 ft/sec. it is known that the surrounding medium offers a resistance numerically equal to the instantaneous velocity. if the mass is driven by f(t) 10 cos (2t), find the equation of motion of the mass and the initial conditions. (do not solve the equation) point 2 feet above the an external force equal to (8) a mass weighing 8 pounds stretches a spring 2 feet. at t= 0 the mass is released from rest from a point 10 feet above the equilibrium position, determine the motion of the mass. the-c