A free-rider problem exists when Group of answer choices people receive a benefit for which they do not need to pay. firms impose a cost on third parties. negative externalities exist. a private good is produced.

Stocks a, b, and c are similar in some respects: each has an expected return of 10% and a standard deviation of 25%. stocks a and b have returns that are independent of one another; i.e., their correlation coefficient, r, equals zero. stocks a and c have returns that are negatively correlated with one another; i.e., r is less than 0. portfolio ab is a portfolio with half of its money invested in stock a and half in stock b. portfolio ac is a portfolio with half of its money invested in stock a and half invested in stock c. which of the following statements is correct? a. portfolio ab has a standard deviation that is greater than 25%.b. portfolio ac has an expected return that is less than 10%.c. portfolio ac has a standard deviation that is less than 25%.d. portfolio ab has a standard deviation that is equal to 25%.e. portfolio ac has an expected return that is greater than 25%.

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.

Explain whether each of the following events increases or decreases the money supply. a. the fed buys bonds in open-market operations. b. the fed reduces the reserve requirement. c. the fed increases the interest rate it pays on reserves. d. citibank repays a loan it had previously taken from the fed. e. after a rash of pickpocketing, people decide to hold less currency. f. fearful of bank runs, bankers decide to hold more excess reserves. g. the fomc increases its target for the federal funds rate.