Answer:
6
Step-by-step explanation:
10, 10, 10, 10, 10, 10. Those are 6 tens
-15 would be the answer because if it's below sea level it would have a negative sign in front of 15
No
No, because 8 - 1 ≠ 27 - 8. So, there is no common difference which is needed in order for the sequence to be arithmetic
7
