Make change from $5, $10 and $20 bills

The customer pays with one bill. Find the change.

1. Something costs $4. You pay with a $5 bill. How much change do you get?
2. Something costs $4. You pay with a $10 bill. How much change do you get?
3. Something costs $2. You pay with a $10 bill. How much change do you get?
4. Something costs $7. You pay with a $10 bill. How much change do you get?
5. Something costs $13. You pay with a $20 bill. How much change do you get?
6. Something costs $5. You pay with a $10 bill. How much change do you get?
7. Something costs $15. You pay with a $20 bill. How much change do you get?
8. Something costs $2. You pay with a $5 bill. How much change do you get?
9. Something costs $8. You pay with a $10 bill. How much change do you get?
10. Something costs $6. You pay with a $10 bill. How much change do you get?
11. Something costs $3. You pay with a $5 bill. How much change do you get?
12. Something costs $3. You pay with a $10 bill. How much change do you get?
13. Something costs $7. You pay with a $20 bill. How much change do you get?
14. Something costs $3. You pay with a $20 bill. How much change do you get?
15. Something costs $14. You pay with a $20 bill. How much change do you get?
16. Something costs $9. You pay with a $10 bill. How much change do you get?
17. Something costs $11. You pay with a $20 bill. How much change do you get?
18. Something costs $8. You pay with a $20 bill. How much change do you get?
19. Something costs $4. You pay with a $20 bill. How much change do you get?
20. Something costs $1. You pay with a $5 bill. How much change do you get?