Which of the following would an economist classify as physical capital?

The real-nominal principle states that

A) what matters to people is the face value of money or income. B) people respond more to explicit, or real, costs than to implicit costs. C) people respond more to implicit costs than to explicit costs. D) what matters to people is the purchasing power of money or income.

Lucinda starts a business consulting company. She makes all the business decisions and bears the risk of running the business. The typical payment for Lucinda's work is ________

A) all the revenue greater than her opportunity cost B) all the revenue greater than the capital investment C) a normal profit D) an economic profit