For the study described below, indicate all the information you can about how the independent variable was manipulated. A psychologist conducted a study to compare the effect of different types of...

For the study described below, indicate all the information you can about how the independent variable was manipulated.

A psychologist conducted a study to compare the effect of different types of displays on participants’ interest in a task. All participants in the study were asked to complete a set of math problems in the laboratory. Half of the participants just saw the text of the problem presented on the screen in black and white and typed in their answer on the computer keyboard. The other half of the participants saw the text of the problem in different colors, and small pictures that helped illustrate the problem were included. At the end of the task, all participants rated their interest in completing the task on a 1 to 10 scale.