For number 1, since the arithmetic means between 5 and 20 are 10 and 15, the first answer found on column is b and since their common difference is 5, the second answer found on column is a. 1. -16 and -22 a. 10 and 16 a a. 5 2.-21 and -6 b. 9 and 13 b.6 3.4 and 22 c. -16 and -11 c. -2 4. 5 and 17 d. 15 and 18 d. 4 5. 12 and 21 e. -18 and -20 e. 3 Rubric for Scoring: Activity 1: One (1) point for every correct response.?​