Question

katie left a balloon in the car overnight. the next morning, she noticed that the balloon had shrunk! it was very cold out, and katie wondered if cooling down inflated balloons causes them to shrink. to find out, katie inflated nine identical balloons to the same circumference. she placed three balloons in a cabinet that was at room temperature of 68°f. she also placed three balloons in a refrigerator, where the temperature was 37°f. she placed the three remaining balloons in a freezer set at 0°f. three hours later, she measured the circumferences of the balloons. complete the sentence. in this experiment, the balloons chilled in the freezer were part of ___ a control group an experimental group

Explanation:

In an experiment, the experimental group is exposed to the variable being tested. Here, the variable is temperature, and the balloons in the freezer are exposed to the low - temperature condition being tested. The control group would be the balloons at room temperature as they are not exposed to the temperature change being studied.

Answer:

an experimental group