A researcher performs an experiment to determine if the loss of sleep affects the ability to maintain constant attention. Fifteen individuals are randomly divided among the following three groups of 5 subjects each: group 1, who sleeps normally (from 7 to 8 hours); group 2, which does not sleep for 24 hours, and group 3, who does not sleep for 48 hours. All three groups are subjected to the same auditory perception test, which consists of making them hear half-second tones at irregular intervals for one hour. In On certain occasions, one tone is slightly shorter than the others. The The subject's task is to detect the shortest tones. Thus observed the following percentages of correct perceptions

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