When can PPC be a straight line?

Related questions

1. Why is a PPF curved instead of straight?
2. How can a production possibilities curve shift outward?
3. What is the shape of PPC and why?
4. What is PPC curve in economics?
5. How does a PPC show unemployment?
6. Why is PPC Convex to origin?
7. What is production possibility frontier PPF or transformation curve and how the curve is derived?
8. What is the difference between PPC and PPF?
9. Is PPC concave or convex?
10. Why is PPC linear?

Tags

1. #shape
2. #opportunity
3. #curve
4. #different
5. #depending
6. #changing
7. #usually
8. #related
9. #constant
10. #directly
11. #points
12. #production
13. #context
14. #below
15. #straight
16. #start
17. #goods