A manufacturer claims that the mean lifetime, u, of its light bulbs is 47 months. The standard deviation of these lifetimes is 8 months. One hundred fifty bulbs are selected at random, and their mean...

(a)	State the null hypothesis H0 and the alternative hypothesis H1 .
H0:
H1:
(b)	Determine the type of test statistic to use.
	▼(Choose one)
(c)	Find the value of the test statistic. (Round to three or more decimal places.)
(d)	Find thep-value. (Round to three or more decimal places.)
(e)	Can we conclude that the mean lifetime of light bulbs made by this manufacturer differs from 47 months?
Yes No

Extracted text: A manufacturer claims that the mean lifetime, u, of its light bulbs is 47 months. The standard deviation of these lifetimes is 8 months. One hundred fifty bulbs are selected at random, and their mean lifetime is found to be 46 months. Can we conclude, at the 0.05 level of significance, that the mean lifetime of light bulbs made by this manufacturer differs from 47 months? Perform a two-tailed test. Then complete the parts below. Carry your intermediate computations to three or more decimal places, and round your responses as specified below. (If necessary, consult a list of formulas.)