It is known that in a chemical process the purity of oxygen is related to the percentage hydrocarbons that are present in the main condenser. The purity of the oxygen in percents was measured in 20 hydrocarbon levels and the following regression summary information were obtained:
Sxx = 0.68
Sxy = 10.18
Syy = 173.37 yy
where the fitted equation is Y = 75.20 14.97X . Based on this,
a. Compute and interpret the correlation coefficient
b. Find the mean square error
c. Find the standard error of the slope
d. With a significance level of 1%, test for the significance of the regression line