A student did an experiment to see how much candy she should use to make rock candy. She made one solution that had 3 parts sugar to one part water (3:1), and another solution that had one part sugar to one part water (1:1). She measured how many grams of candy was formed. The results are on the chart below What were the variables that the student need to control in this investigation? (check all that apply)
A. the temperature in the room
B. how hot the water was that she used
C. how much food coloring she used
D. the amount of sugar used