What is the difference between economies of scale and returns to scale? a. economies of scale are present when the expansion path is a straight line, and returns to scale are present when the expansion path is not a straight line. b. economies of scale define how cost changes with output, and returns to scale define how output changes with input usage. c. economies of scale are present when the long-run average cost curve is increasing, and returns to scale are present when the long-run average cost curve is decreasing. d. economies of scale define whether joint output of a single firm is greater than output that could be achieved by two different firms when each produces a single product, and returns to scale define how output changes with input usage for a single firm. e. economies of scale define how cost changes with output in the long run, and returns to scale define how cost changes with output in the short run.

Payday loans could be considered as a. illegal b.subprime lending c. good deal for borrower d. for frequent use

Following is a list of various costs incurred in producing replacement automobile parts. with respect to the production and sale of these auto parts, classify each cost as either variable costs, fixed costs, or mixed costs. 1. oil used in manufacturing equipment 2. plastic 3. property taxes, $165,000 per year on factory building and equipment 4. salary of plant manager 5. cost of labor for hourly workers 6. packaging 7. factory cleaning costs, $6,000 per month 8. metal 9. rent on warehouse, $10,000 per month plus $25 per square foot of storage used 10. property insurance premiums, $3,600 per month plus $0.01 for each dollar of property over $1,200,000 11. straight-line depreciation on the production equipment 12. hourly wages of machine operators 13. electricity costs, $0.20 per kilowatt-hour 14. computer chip (purchased from a vendor) 15. pension cost, $1.00 per employee hour on the job

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.