Is the position of a particle moving along a straight line at time t. (a) Find the velocity and acceleration of the particle. (b) Find all times in the given interval when the particle is stationary. On the way down, and 2 seconds after that, it hits the ground below. A. What is the initial velocity of the ball? B. How high is the building? C. What is the velocity of the ball when it passes you on the way down? D. What is the velocity of the ball as it hits the ground?