Activity 2. Which of the following is an arithmetic sequence? Mark check (T) if it is an arithmetic sequence and X if it is not on the space provided before the number 1. 5, 10, 15, 20, 2. 4 7 10 13 3. 4, 9, 14, 19, 4. 10,5, 0,-5,-10,-15 5. 3,6, 12, 24, *what is the answer