A ball is tossed straight upward from ground level. A student chooses downward as the positive y-direction. Which of the following lists the signs of the ball’s velocity and acceleration at the instant the ball reaches its highest point?
a) Velocity = 0\,m/s, Acceleration = 0
b) Velocity = positive, Acceleration = positive
c) Velocity = 0\,m/s, Acceleration = positive
d) Velocity = 0\,m/s, Acceleration = negative