Homework4: Problem 4 Problem L Results for this submission [ Entered Answer Preview Result 265 25.5 The answer above IS NOT correct.

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Homework4: Problem 4 Problem L Results for this submission [ Entered Answer Preview Result 265 25.5 The answer above IS NOT correct. (1 point] A medical researcher wants to investigate the amount oi time it takes for patients‘ headache pain to be relieved afler taking a new prescription painkiller, She plans to use statistical methods to estimate themean of the population of relief times, She believes that the population is normally distributed with a standard deviation of 18 minutes, How large a sample should she take to make an estimate within 2minutes of the mean time with 93% confidence?