you are so wise how do you do it?
When the ball reaches its original position, it will have the same speed (but would be traveling in the opposite direction). So the average speed is

regardless of how long the ball was in the air.
The answer that would best complete the given sentence above is cubic meter. The standard unit for measuring volume is the cubic meter (m^3). Volume is the quantity or the measurement of the amount of space that can be or is being occupied by matter. The metric unit for volume includes "liters" and "milliliters".
(20 seconds / 40 vibes) = (20/40) (seconds/vibe) = 0.5 second