) 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

2) What question is mare most likely investigating?

a. what effect does temperature have on rate of evaporation?
b. which material makes the best insulator ?
c. how quickly do different amounts of water cool?
d. how longs does it take for 50 ml of water to reach room temperature

3)What would be the best way fro mara to display results of this investigation?

a. a pie chart
b. a stem and leaf plot
c. a line graph
d. venn diagram

4 answers

I will be happy to critique your thinking.
1-B
2-B
3-C
I agree on 1 and 2, on 3 none are good methods. I would have used a bar chart. I suppose a line chart is a near relative, but I wouldn't use it.
The independent variable is D (The material the cups are made of). An independent variable is what is changed! The amount of water in each cup is the same...50mL, so that is the control group.