NEED HELP ASAP!!! 15 POINTS Poison ivy is a weed that synthesizes an oil, urushiol, that causes skin rashes. Researchers have found that if poison ivy grows in an environment that contains an increased concentration of carbon dioxide, the plants grow larger, faster, and produce more urushiol. To test this idea, researchers create an experiment where different experimental groups of poison ivy are exposed to different concentrations of carbon dioxide to determine how tall they will grow.

Identify two conditions that should be kept the same for control and experimental groups.​