Which three investigations will provide evidence to support what they have learned?

measuring how close a soda can must be before it rolls toward a balloon that has been rubbed on someone's hair
counting the number of staples that are directly attached to a strong magnet
dropping a rubber ball from a distance of 1.5 meters above the classroom floor
placing a magnet against a jar containing a mixture of iron filings and sand
measuring how far a toy car travels across the floor before coming to a stop