Question

Couldn’t figure out.

Answer 1

It’s the third one since the way arithmetic sequence I mean by finding the common difference is subtracting the second element by the first one so I chose {1,4,7,10…..} because if I subtract 4 by 1 it’s 3 so it all goes since it applies with the other elements I mean…
4+3=7 and 7+3 =10

Hope you understand.

Answer 2

Answer is (1, -2, 4, -8…..) and (1, 3, 9, 27…..) and (1, 4, 7, 10…..)

Explanation - arithmetic sequence means the difference between the consecutive terms is constant / the same.
(1, -2, 4, -8…..).

Each number is multiplied by -2 creating a sequence.

(1, 3, 9, 27…)

Each number is multiplied by 3 creating a sequence.

(1, 4, 7, 10…)

Each number is +3 creating a sequence.

Problem solved