In the past, the mean running time for a certain type of flashlight battery has been 8.1 hours. The manufacturer has introduced a change in the production method and wants to perform a hypothesis test to determine whether the mean running time has changed as a result. This test would be a

(a) left-tailed test

(b) two-tailed test

(c) right-tailed test

1. The test is(Enter a, b, or c)

2

The recommended dietary allowance (RDA) of vitamin C for women is 75 milligrams per day. A hypothesis test is to be performed to decide whether adult women are, on average, getting less than the RDA of 75 milligrams per day. This test would be

(a) left-tailed

(b) two-tailed

(c) right-tailed

The test is(Enter a, b, or c)

3

The maximum acceptable level of a certain toxic chemical in vegetables has been set at 0.6 parts per million (ppm).A consumer health group measured the level of the chemical in a random sample of tomatoes obtained from one producer to determine whether the mean level of the chemical in these tomatoes exceeds the recommended limit. This test would be

(a) left-tailed

(b) two-tailed

(c) right-tailed

The test is(Enter a, b, or c)