Solve the following by describing a picture, and by constructing a graph:

1.  If your total earnings up to week 6 are 71.07879 dollars, and your total earnings up to week 14 are 83.07879 dollars, then what are your average earnings per week? Why do we say average earnings per week rather than just earnings per week?

2.  If an automobile is at milepost 421.4492 after having traveled for 8 hours and at milepost 475.4492 after having traveled for 15 hours, then what is its average speed? Why do we say average speed rather than just speed?

3.  If the water in a uniform cylinder has depth 199.345 cm at clock time 7 seconds and depth 228.345 cm at clock time 16 seconds, then at what average rate is the depth changing? What we say average rate rather than just rate?

4.  If you are earning money at an average rate of 15 dollars per week, and if at the end of week 9 your total earnings are 133.16 dollars, then what will be your total earnings that the end of week 17?

5.  If an automobile is traveling at the rate of 48 mph, and is at milepost 285.7328 after having traveled for 6 hours, then what milepost would be after having traveled for 11 hours?

6.  If the depth of water in a uniform cylinder is changing at an average rate of 21 cm/second between clock times 9 s and 19 s, and if its depth at clock time 9 seconds is 178.7489 cm, then what is its depth at clock time 19 seconds?

7.  If your total earnings up to week 4 are 20.91871 dollars, and if you earn money at a constant rate of 6 dollars per week, then at what week will your total earnings be 26.91871 dollars?

8.  If an automobile is traveling at the rate of 51 mph, and is at milepost 202.9944 after having traveled for 4 hours, then after how many hours of travel will it have reached milepost 15?