The marginal benefit of an additional beach towel is $12 the marginal cost of producing an additional beach towel is $8 as producers are minimizing the average cost of production and we can conclude. a. beach towel production is allocatively efficient than not productively efficient. b. beach tower production is not allocatively efficient but is productively efficient. c. beach towel production is neither allocatively nor productively efficientd. beach towel production is both allocatively and productively efficient

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%.