Exercise A (p.4) No. 1

1. false

2. false

3. true

4. true

5. false

6. true

7. true

8. false

9. {1,4,5,6,7,8,9,...} true

10. {...,-4,-3,-2,-1,0,1,3,4,...} false

11. {-1,0,1,2} true

12. {-2,-1,0,1,2,3,4} false

13. {-1,0,1,2,3,4,5} true

14. only integers given, no real numbers, false

15. {...,-1,0,1,2} true

16. all real numbers between 2 and 3 missing, false