1.      research institute reported that the average number of weeks an individual is unemployed is 17.5 weeks. Assume that for the population of all unemployed individuals the population mean length of unemployment is 17.5 weeks and that the population standard deviation is 4 weeks. Suppose you would like to select a random sample of 50 unemployed individuals for a follow-up study.
a.       What is the probability that a simple random sample of 50 unemployed individuals will provide a sample mean of   less than 1 week?
b.       What is the probability that a simple random sample of 50 unemployed individuals will provide a sample mean within 1 week of the population mean?
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