2.  Recall, in an sequence, the difference between consecutive terms is constant. The constant difference is called the difference and is denoted by d.  The nth term of an arithmetic sequence with first term and common difference d is given by: arithmetic common

3. 1. 2.

4. 3.

5. 4.

6. 5.

7. 6.

8. 7.

9. 8.

10. 9.

11.  The terms between two given terms of an arithmetic sequence are called between the given terms. arithmetic means

12. 10.three between 5 and 23

13. 11.nine between -17 and -2

14.  12. The first tread of a flight of stairs is 22 cm above the ground. If each thread after the first is 15.5 cm above the level of the previous step, how high above the ground is the thread of the 19 th step?

15.  13. At the University of Arizona, the starting salary for a professor is $13,000 with an annual raise of$1,150 each year until the maximum salary of $29,100 is reached. How many years must a person teach in order to reach the maximum salary?