A biologist gives a new kind of food to a group of dogs and compares the weight gain of these dogs over time to a group of similar dogs that do not receive the new food.

1) a

2)c

3)a

4)c

5)b

hope this , if so, your appreciation would be signified through giving   me brainliest, and a you : ) have any further questions? feel   free to ask me in the questions box.