10) In order to set rates, an insurance company is trying to estimate the number of sick days that full time workers at an auto repair shop take per year. A previous study indicated that the standard deviation was 2.8 days. How large a sample must be selected if the company wants to be 95%confident that the true mean differs from the sample mean by no more than 1 day? A) 31 B) 512 C) 1024 D) 141

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