Dullco Manufacturing claims that its alkaline batteries last at least 40 hours on average in a certain type of portable CD player. But tests on a random sample of 18 batteries from a day's large production run showed a mean battery life of 37.8 hours with a standard deviation of 5.4 hours. To test DullCo's hypothesis, the p-value is:
A)slightly less than .05.
B)exactly equal to .05.
C)slightly greater than .05.
D)uncertain without knowing α.

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The Answer of Dullco Manufacturing claims that its alkaline batteries last at least 40 hours on average in a certain type of portable CD player. But tests on a random sample of 18 batteries from a day's large production run showed a mean battery life of 37.8 hours with a standard deviation of 5.4 hours. To test DullCo's hypothesis, the p-value is:
A)slightly less than .05.
B)exactly equal to .05.
C)slightly greater than .05.
D)uncertain without knowing α.

Dullco Manufacturing Claims That Its Alkaline Batteries Last at Least