Afree falling rock is released at an altitude of 50 m. earth's gravity g = 9.81 m/s^2 is the only force acting upon the rock. (i. e. no atmospheric drag). plot the altitude, velocity, and acceleration as a function of time (4 seconds in 0.05 second steps) in one figure using the "subplot" function. in a second figure plot the velocity as a function of the altitude.