Students set up a controlled experiment. They put five crickets in each of three identical containers. They set one
container to 15°C, one to 20°C, and one to 25°C. Then they
count the number of cricket chirps in each container
during 1 hour
What are two constants in this experiment?
A. The number of crickets in each container
B. The number of cricket chirps
O C. The kind of containers used
D. The temperature of each container

How is electrolysis most commonly used to produce an energy source? a - splitting water molecules produces oxygen, which organisms breathe to fuel their bodies. b - splitting water molecules produces hydrogen gas, which is used to power machines through hydrogen fuel cells. c - splitting carbon dioxide molecules produces coal, a form of carbon that can be burned to produce heat. d - splitting carbon dioxide molecules produces natural gas, which can be burned to generate electricity in power plants.