26. Expedia would like to test that the average number of Southwest Airlines flights which arrive on time (µ) is 90. A random sample of 140 flights found that 119 arrived on time. Suppose a = 0.05. Then the critical value for the test %3! (Za/2) is a) 1.28

Given that Z is distributed as a standard normal random variable, what is Pr(Z > -0.04)? Round your answer to three decimal places, e.g. 0.251.

A bakery has determined that the number of loaves of its white bread demanded daily has a normal distribution with mean 7,200 loaves and standard deviation 300 loaves. Based on cost considerations, the company has decided that its best strategy is to produce a sufficient number of loaves so that it will fully supply demand on 94% of all days. a. How many loaves of bread should the company produce? b. Based on the production in part (a), on what percentage of days will the company be left with more than 500 loaves of unsold bread?

The error term is heteroskedastic if var(uil Xi = x) depends on x. var(uil Xi = x) is constant for i = 1,..., n. Xi is normally distributed. there are no outliers.