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

1.  If your total earnings up to week 7 are 100.2417 dollars, and your total earnings up to week 14 are 115.2417 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 6 dollars per week, and if at the end of week 7 your total earnings are 41.48305 dollars, then what will be your total earnings that the end of week 18?

3.  If your total earnings up to week 8 are 47.62547 dollars, and if you earn money at a constant rate of 6 dollars per week, then at what week will your total earnings be 53.62547 dollars?

4.  If an automobile is at milepost 239.259 after having traveled for 5 hours and at milepost 287.259 after having traveled for 14 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 75 mph, and is at milepost 652.268 after having traveled for 9 hours, then what milepost would be after having traveled for 14 hours?

6.  If an automobile is traveling at the rate of 62 mph, and is at milepost 367.3219 after having traveled for 6 hours, then after how many hours of travel will it have reached milepost 16?

7.  If the water in a uniform cylinder has depth 343.1108 cm at clock time 10 seconds and depth 378.1108 cm at clock time 15 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 9 cm/second between clock times 8 s and 18 s, and if its depth at clock time 8 seconds is 71.18548 cm, then what is its depth at clock time 18 seconds?