Answer:
+ 8
Explanation:
This is an arithmetic progression (AP) as there is a common difference between successive terms.
For example, looking at the first two terms,
Difference = 2nd term - 1st term
= -11 -(-19)
= -11 + 19
= +8
To check,
Looking at the second and third terms,
Difference = 3rd term - 2nd term
= -3 -(-11)
= -3 + 11
= +8
Hence, there is a common difference of +8 between consecutive terms, making it an AP.