1. a manufacturer claims that the mean lifetime of its fluorescent bulbs is 1500 hours. a homeowner selects 40 bulbs and finds the mean lifetime to be 1480 hours with a population standard deviation of 80 hours. test the manufacturer's claim. use alpha equal to 0.05. state the sample mean and the population standard deviation.

2. using problem in number 1. choose the correct hypotheses.
3. using the problem in number 1. state the critical value(s).
4. using the problem in number 1. state the test statistics.

a.) -1.96
b.) -2.00
c.) 1.58
d.) -1.58

5. using the problem in number 1. state the decision.

a.) fail to reject ha
b.) reject h0
c.) reject ha
d.) fail to reject h0

6. using the problem in number 1. state the conclusion.

a.) there is not enough evidence to support the claim that the mean lifetime of its fluorescent bulbs is 1500 hours.
b.) there is enough evidence to support the claim that the mean lifetime of its fluorescent bulbs is 1500 hours.
c.) there is not enough evidence to reject the claim that the mean lifetime of its fluorescent bulbs is 1500 hours.
d.) there is enough evidence to reject the claim that the mean lifetime of its fluorescent bulbs is 1500 hours.