Final answer:
The sequence given does not have a consistent common difference between its terms, indicating it is not an arithmetic sequence.
Step-by-step explanation:
The question asks for the common difference between successive terms in the provided sequence: 2.8, 14, 20, 20. To find the common difference, we need to subtract each term from the one that follows it.
- 14 - 2.8 = 11.2
- 20 - 14 = 6
- 20 - 20 = 0
There appears to be no consistent common difference between each pair of successive terms, which means this sequence is not an arithmetic sequence.