Determine whether the given sequence is arithmetic, geometric, or neither. If the sequence is arithmetic, give the common difference; if it is geometric sequence, give the common ratio.

1. 8, 12, 16, . . .
2. 1, 3, 9, 27, . .
3. 1000, 100, 10, . . .
4. -3, -1, 1, 3, . . .
5. 1, 4, 16, 64, . . .
6. 2 3 , 3 4 , 4 5 , . . .
7. 5, 15, 45, . ..
8. −8, 8, −8, . ..
9. 2, 4,8,10,. . .
10.10, -5, 1, . . . ​