Sentences were chosen at random from Muhammad ibn Musa al-Khwarizmi's book The Compendious Book on Calculation by Completion and Balancing. The number of words in the sentences were counted. This is the result.

12

16

6

5

5

3

7

10

22

20

22

5

5

21

18

22

9

16

10

6

17

12

3

14

Problem:

Use the data above to: a) determine the mean and sample standard deviation, b) calculate a 95% margin of error, c) determine the respective confidence interval.