For Exercises 7.75 and 7.76, see page 402; for 7.77 and 7.78, see page 404; for 7.79 and 7.80, see page 406; and for 7.81 see page 408.
7.80 Power and the standard deviation
If the true population standard deviation were 25 instead of the 19.59 hypothesized in Example 7.19, would the power increase or decrease? Explain.