Height of players Color of the baseballs thrown Order in which the players throw Spot from which players throw
I am hesitating between 4 options to answer the following question, which option should I choose?
Question: Three baseball players investigate to see who can throw a baseball the farthest. They mark off an area on the playground for their investigation. Which should they keep constant?
Possibilities:
- Height of players
- Color of the baseballs thrown
- Order in which the players throw
- Spot from which players throw

Spot from which players throw