Jen is standing on top of a 52 meter high building. She threw a rock straight downward at 18m/s. How fast will the rock be traveling when it hits the ground? Determine how long it will take for the ball to hit the ground? my attempt: I got 31.45m/s as the speed of the rock and 1.402 seconds to hit the ground, but I don't think I did it right. Can someone please help me out?