A new light bulb is being considered for use in an office wi

A new light bulb is being considered for use in an office with computers. It is decided that the new bulb will only be used if it has a mean lifetime of more than 500 hours. A random sample of 40 bulbs is selected and placed on life test. The mean and standard deviation are found to be 505 hours and 18 hours, respectively. Use a 0.01 level of significance. The hypothesis to be tested is: H0: mu=500 vs. Ha: mu>500 The test statistic is: z=1.76 Please state the correct conclusion.

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