【单选题】According to Mr. Hall, what is opportunity cost?
A.
It is the relationship between two kinds of goods or services that customers may want to buy.
B.
It is people's choice of goods and services at similar prices.
C.
It is the relative value of goods to buyers compared to the value of alterative goods and services on which they may want to spend that same amount of money.
【简答题】Suppose that your college charges you separately for tuition and for room and board. A. What is a cost of attending college that is not an opportunity cost? B. What is an explicit opportunity cost of ...