The material used in this profect are waterballoons to drop from different heights, stopwatch to record the time, meterstick to measure the heights of the three different levels, and a launcher to drop the balloons.
(The material; used; L:in this profect) (The material used in this profect; are; waterballoons)
The material The material used in this profect
used are
L:in this profect
waterballoons