2. The height of the ramp is . Use Pythagorean theorem to calculate the length of the ramp. I got
3. Using the formula for d I got as the acceleration time. Since the motion is symmetric this is the time for deceleration too.
4. The speed of the ball at the foot of the ramp is . With this speed the ball needs 1.46 s to pass the 6 m horizontal distance.
5. The total time of the complete movement is therefore 4.5 s.