Explanation:
because it allows you to eliminate or isolate variable/ it allows the experiment to minimize the changes in all the variables except the one being test.
I'm not gonna choose bc I'm not 100% sure either so read what's above, think it over and choose wisely
hope I helped a little and good luck :)
Answer:
but you got to figure it out
Answer:
:-) maintaining the pH of the reaction at 6.7
Explanation:
hope this helps
It would be the respiratory system