A group of children is given special training on how to handle their anger. A second group is treated the same as the first group except they do not receive the special training. Those given the training comprise the , and those who receive no training comprise the .

experimental group; control group

Explanation:

 An experimental group also called a treatment  group  in which involves a group is being exposed to receive experimental conditions, here the group is exposed to the experimental independent  variable to test for reactions and the changes in reaction are being recorded.The group of children given special training to handle anger is the experiment group

A control group is a group which is isolated from an experiment in which the group is not exposed to any treatment conditions and reactions are recorded. The control group helps to  check validity of the entire experiment conducted The group of children that  do not receive the special training.

your answer would b. the missisipi river

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