Paint used to paint lines on roads must reflect enough light to be clearly visible at night. Let µ denote the true average reflectometer reading for a new type of paint under consideration. A test of H0: µ = 20 versus Ha: µ > 20 based on a sample of 11 observations gave t = 3.2. What conclusion is appropriate at each of the following significance levels?

(c) a = .001

Explanation is greatly appreciated

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