Why is it important to keep every variable (constants) the same, or controlled except
the variable being tested.
It is important to keep all variables the same
except the one being tested, so you know if the
tested variable is responsible for the effect.
It isn't important to keep variables the same.

Which of the following warnings would an agricultural chemist tell a farmer who wants to recycle his or her own ammonia? recycling ammonia is a difficult process that sometimes takes weeks. recycling ammonia requires a degree in biochemistry or a related field. recycling ammonia can be harmful because it is highly flammable and toxic. recycling ammonia costs too much money considering the price of the necessary chemicals.