`80, 40, 20, 10, 5, ...` Determine whether the sequence is arithmetic. If so, find the common difference.

Given the sequence: 80, 40, 20, 10, 5

The sequence is not arithmetic. The difference between consecutive terms is not common.

Given the sequence: 80, 40, 20, 10, 5

The sequence is not arithmetic. The difference between consecutive terms is not common.