When nicotine is absorbed by the body, cotinine is produced. A measurement of cotinine in the body is therefore a good indicator of how much as person smokes. Listed below are the reported numbers of cigarettes smoked per day and the measured amounts of nicotine (in ng / ml). (The values are from randomly selected subjects in the National Health Examination Survey). Is there a significant linear correlation? Explain the result. Use the rank correlation coefficient to test for a correlation between the two variables and explain via scatterplots why the rank correlation is preferred in this context.

X (cigarettes/day)	60	10	4	15	10	1	20	8	7	10	10	20
Ranks of X	12	6.5	2	9	6.5	1	10.5	4	3	6.5	6.5	10.5
Y (cotinine)	179	283	75.6	174	209	9.51	350	1.85	43.4	25.1	408	344
Ranks of Y	7	9	5	6	8	2	11	1	4	3	12	10