Determine if the sequence is arithmetic. If it is, find the common diference and the three terms
in the sequence after the last one given.
1) -24, 6, 36, 66.

2) 16, 24. 32. 40,

3 1-1. 1.-1.

4) 31, 24, 17, 10. ...

5) -20, -26, -32. -38,

6 11, 21, 31, 41,..

7) 4. 12. 20, 28, ...

8) 20, 14, 8, 2,.