Mr. Smith designed an experiment to see which group of students would test the highest. He set
up three groups of 25 students. Group A did not
study for the test, group B studied for 5 hours, and
group C studied for 10 hours.
Which group is the control group?
A. Group A
B. Group B
C. Group C
D. There is no control group
of 3

Why are carbon dioxide concentrations expected to increase? a carbon dioxide concentrations are expected to increase, because fossil fuel burning is expected to increase b. carbon dioxide concentrations are expected to increase, because of an increase in agriculture. c.carbon dioxide concentrations are expected to increase, because more land will have to be cleared for increasing populations and agricultural use. d. all of the above select the best answer from the choices provided mark this and return save and exit next submit submit