# Question: A sample of n 40 is selected from a

A sample of n = 40 is selected from a normal population with µ = 75 msec. and s = 12, and a treatment is administered to the sample. The treatment is expected to increase scores by an average of 4 msec.

a. If the treatment effect is evaluated with a twotailed hypothesis test using a = .05, what is the power of the test?

b. What is the power of the test if the researcher uses a one-tailed test with a = .05?

a. If the treatment effect is evaluated with a twotailed hypothesis test using a = .05, what is the power of the test?

b. What is the power of the test if the researcher uses a one-tailed test with a = .05?

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