Complex sentence: Dill and Anderson present a study that questions whether frustration that is justified or not plays a role on future aggression condition the experimenter states how they will only present the instructions one time and then start the timer.
Split into simpler sentences: Dill and Anderson present a study that questions whether frustration that is justified or not plays a role on future aggression. In each condition the experimenter states how they will only present the instructions one time and then start the timer.