A new sunscreen has been developed that is supposed to be more effective at preventing sunburn. 30 participants spray one arm with the new formula, and spray the other arm with the leading formula. After 4 hours in the sun, their skin is evaluated for any redness. What is the purpose of the experiment? Identify the independent variable. Identify the dependent variable. Describe the first group of people in the experiment. Describe the second group of people in the experiment. Identify two factors which are kept constant( same). Which group is the test group? Which group is used for comparison?

Explanation:

This question appears incomplete but can however still b answered.

The purpose of the experiment is to test the effectiveness of the new sunscreen.

An independent variable is the variable that is changed (directly or indirectly) during the course of an experiment. The independent variable here are the sunscreen.

A dependent variable is the variable that is been tested in the course of the experiment. The dependent variable here is the redness of the skin.

The first group here (this could be in the missing part of the question, hence response not certain) is the control group. The control group consists of the arms sprayed with the leading/old sunscreen formula.

The second group is the test group. It consists of the arms sprayed with the new sunscreen formula.

The factors that are kept constant (or control variable) are the duration under the sun (4 hrs) and the participants' arms used.

The test group is the second group while the group used for comparison (to be sure the new sunscreen is more effective) is the first group.