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 the amount of living space and the amount food each rat received. each day the student measured and recorded the weight of each rat. state one major error that student made in performing this investigation.

he amount of living space for the rats and the amount of food are two different variable that will make a  mistake the student changed. If you're doing an experiment, you need to control the conditions and the only change ONE variable at a time of each one . If you want to know if the food and the living space affect weight, you should do two different experiments.

i hope this helps you out

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