After Swimming 100 Laps at the Pool, Erik Decides to Swim

question 71

Multiple Choice

After swimming 100 laps at the pool, Erik decides to swim 10 more before lifting weights. This statement best represents this economic concept:

• A)Resources are scarce.
• B)The real cost of something is what you must give up to get it.
• C)"How much" is a decision at the margin.
• D)There are gains from trade.