In what ways can a monopolistically competitive firm differentiate their product?

The social rate of discount is best approximated by:

a. the cost of government borrowing b. the opportunity cost of resources taken from the private sector c. 3 percent d. 30 percent e. none of the above

The opportunity cost of an activity is

a. zero if you choose the activity voluntarily b. the amount of money spent on the activity c. the value of the best alternative not chosen d. the sum of benefits from all of the sacrificed alternatives e. the difference between the benefits and the costs of that activity