posted by Leah .
Mare is preparing an experiment using 3 cups, one made of paper, one of plastic and one of glass. She plans on pouring 50 ml of hot water from a pitcher into each of the 3 cups and record the temperature in 5 minute intervals. What is the independent variable in this investigation?
a. the time interval between measurements
b. the amount of water in each cup
c. the initial temperature of the water in the cups
d. the material the cups are made of