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

1.  If your total earnings up to week 6 are 88.20547 dollars, and your total earnings up to week 15 are 103.2055 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 251.6312 after having traveled for 7 hours and at milepost 287.6312 after having traveled for 17 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 32.96356 cm at clock time 4 seconds and depth 42.96356 cm at clock time 13 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 6 your total earnings are 88.52328 dollars, then what will be your total earnings that the end of week 17?

5.  If an automobile is traveling at the rate of 41 mph, and is at milepost 243.1118 after having traveled for 6 hours, then what milepost would be after having traveled for 15 hours?

6.  If the depth of water in a uniform cylinder is changing at an average rate of 12 cm/second between clock times 7 s and 13 s, and if its depth at clock time 7 seconds is 74.18938 cm, then what is its depth at clock time 13 seconds?

7.  If your total earnings up to week 5 are 67.2278 dollars, and if you earn money at a constant rate of 14 dollars per week, then at what week will your total earnings be 81.2278 dollars?

8.  If an automobile is traveling at the rate of 55 mph, and is at milepost 474.611 after having traveled for 9 hours, then after how many hours of travel will it have reached milepost 19?