2)Choose one of the shapes which will touch the bottom first.
1)There were three different sizes.
We chose the middle-sized ball but in the end the largest ball was the fastest.
Through the process,we used the formula '(mg-u)-kv=ma'.
(mg-u) is always constant ,v refers to volume,m refers to mass and a refers to acceleration.
2)There were different shapes
we chose the shape that looked like a tablet or diamond but in the end the sphere was the fastest.
This is because along the way,the figures changed its direction.Since the sphere has a fixed shape,it was less affected by the resistance.