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

1.  If your total earnings up to week 4 are 37.53974 dollars, and your total earnings up to week 9 are 47.53974 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 you are earning money at an average rate of 10 dollars per week, and if at the end of week 6 your total earnings are 58.25712 dollars, then what will be your total earnings that the end of week 17?

3.  If your total earnings up to week 9 are 102.4796 dollars, and if you earn money at a constant rate of 12 dollars per week, then at what week will your total earnings be 114.4796 dollars?

4.  If an automobile is at milepost 153.7267 after having traveled for 4 hours and at milepost 193.7267 after having traveled for 15 hours, then what is its average speed? Why do we say average speed rather than just speed?

5.  If an automobile is traveling at the rate of 60 mph, and is at milepost 472.0853 after having traveled for 8 hours, then what milepost would be after having traveled for 16 hours?

6.  If an automobile is traveling at the rate of 37 mph, and is at milepost 177.7523 after having traveled for 5 hours, then after how many hours of travel will it have reached milepost 16?

7.  If the water in a uniform cylinder has depth 60.97905 cm at clock time 4 seconds and depth 77.97905 cm at clock time 14 seconds, then at what average rate is the depth changing? What we say average rate rather than just rate?

8.  If the depth of water in a uniform cylinder is changing at an average rate of 22 cm/second between clock times 10 s and 16 s, and if its depth at clock time 10 seconds is 200.3037 cm, then what is its depth at clock time 16 seconds?