1. Mallory decides to watch a movie at a theatre with her friends instead of working at her job for three hours where she would have earned $15 an hour. The movie ticket cost $20. What was her opportunity cost of going to the movie? 
2. 
   
3. A. 65 
4. 
   
5. B. 15 
6. 
   
7. C. 35 
8. 
   
9. D. 20 
10. 
    
11. E. 45