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using correlational design This means to study whether an increase or decrease in one variable corresponds to an increase or decrease in the other variable so the higher the grades the higher the music. In Quasi- experimental design With random assignment, participants have the same chance of being assigned to the intervention group or the comparison group. so basicaly different students are tested with different exams with different loudness of music.Best way to design an experiment in psychology is to divide the participants into two groups, the experimental group and the control group, and then introduce a change to the experimental group and not the control group.
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