Question

1. in an investigation to determine a factor that affects the growth of rats, a student exposed 100 rats of the same age and species to identical conditions, except for amount of living space and amount of food each rat received. each day the student measured and recorded the weight of each rat. state one major error the student made in performing this investigation. wrong answer: the amount of living space and the amount of food. an experiment should only change one variable at a time and keep all other conditions the same. how can this be made more correct?

Explanation:

The major error is having two independent variables (living - space and food amount) simultaneously. To correct, either keep the amount of living space constant and vary only the amount of food, or keep the amount of food constant and vary only the amount of living space. This way, it's clear which variable is affecting the growth (weight) of the rats.

Answer:

The student had two independent variables (amount of living space and amount of food) changing at the same time. To correct, vary only one variable at a time while keeping the other constant.