Suppose you have $200 with which you can buy shares of stock from two companies: ABC Hot Chocolate Company and XYZ Lemonade. Each company's stock currently sells for $100 per share. If the temperature next year is lower than average, the stock price for ABC will increase by $20, and the stock price for XYZ will not change. If the temperature next year is higher than average, the stock price for XYZ will increase by $20, and the stock price for ABC will not change. There is a 50% chance that it will be colder than average next year, and a 25% chance that it will be warmer than average. If you purchase one share of ABC stock and one share of XYZ stock, your expected gain will be ________.

Which would be considered an investment, according to economists?

A. The sale of a retail department store building by Sears to JCPenney. B. The purchase of newly issued shares of stock in Dell. C. The construction of a new plant by Ford. D. Public transfer payments.

The cost of running an electrical utility includes costs for fuel, labor, and capital. In addition, there are sometimes costs associated with pollution from the utility, such an increased health care costs for people living near the utility. To an economist, the costs associated with the pollution resulting from additional electricity are:

A. marginal social costs. B. marginal private costs. C. the sum of marginal social costs and marginal private costs. D. the difference between marginal social costs and marginal private costs.