Question 6 (20 pts.) River Hills Hospital is interested in determining the effectiveness of a new drug for reducing the time required for complete recovery from knee surgery. Complete recovery is measured by a series of strength tests that compare the treated knee with the untreated knee. The drug was given in varying amounts to 18 patients over a 6-month period. For each patient the number of drug units, X, and the days for complete recovery, Y, are given by the following (x, y) data: (a) (5 pts.)Compute the covariance. (b) (5 pts.)Compute the correlation coefficient. (c) (10 pts.)Briefly discuss the relationship between the number of drug units andthe recovery time. What dosage might we recommend based on this initialanalysis?

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