Abusiness that repairs major appliances charges a flat fee and hourly amount plus the cost of any needed parts. they know that the time required to repair an appliance has a standard deviation of 0.25 hours. the mean depends on the type of appliance. to estimate the true mean time required to repair side-by-side refrigerators, they will take a random sample of 60 refrigerator repairs. if they want a 99% confidence interval, what will the margin of error in their estimate be?

Alarge university wanted to study the relationship between completing an internship during college and students' future earning potential. prom the same graduating class, they selected a random sample of 80 students who completed an internship and 100 students who did not complete an internship and examined their salaries five years after graduation. they found that there was a statistically higher mean salary for the internship group than for the noninternship group. which of the following interpretations is the most appropriate? a. there could be a confounding variable, such as student major, that explains the difference in mean salary between the internship and no internship groups.b. we cannot infer anything from these data since the distribution of salaries is likely right skewed.c. you cannot draw any valid conclusions because the sample sizes are different.d. more students should complete internships because having an internship produces a higher salary.

Amethod of allocating merchandise cost that assumes the first merchandise bought was the first merchandise sold is called the a. last-in, first-out method. b. first-in, first-out method. c. specific identification method. d. average cost method.

In a perfectly competitive market, the long-run market supply curve tends to be horizontal or nearly so. what is another way to state this fact? (a) market supply is much more elastic in the long run than the short run. (b) in the long run, average total cost is minimized. (c) in the long run, price equals marginal cost. (d) market supply is much less elastic in the long run than the short run.