d) A company tests whether telecommuting reduces the number of employee sick days. Historical data shows that on average, employees of the company take 5.4 sick days each year. After instituting telecommuting for a year, it is observed that employees average 4.5 sick days with a standard deviation of 2.7 days. Let u represent the mean number of sick days for all employees of the firm with telecommuting. State an appropriate null hypothesis in terms of u to test whether the telecommuting policy has in fact reduced the number of sick days. You do not need to do the full test; just state the hypothesis. HO:
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