3. The output voltage for an electric circuit is specified to be 130. A sample of 40 independent reading on the voltage for this cimuit gave a sample mean 128.6 and a sample standard deviation 3.9. (a) Is there sufficient evidence to indicate that the average output voltage, is less than 130? Use a large-sample test with significance level = .05. [Sol] (b) Calculate associated p-value in (a). What can said about the calculated p-value? [Sol]