Answer:
idk bud i think its true but it may be false
Explanation:
Answer:
Outside factors are not always constant meaning that there is little way to control them.
Explanation:
Answer:
For several months, weighing and measuring the pups every week
Explanation:
This is to control variables and keep a measurable set of data that can prove or disprove the theory they had developed, and also to isolate cases that can't be attributed to the experiment they had carried out, like puppies loosing weight due to illnesses, or behavioral factors.
