4. For this problem, use the “plastic hardness” data described in the text with problem 1.22 onpage 39. (CH01PR22.DAT) Make sure you understand which column isXand which isYandread in the data accordingly.(a) Plot the data usingPROC GPLOT. Include a regression line on the plot (i = rl). Is therelationship approximately linear?
(b) Run the linear regression to predict hardness from time. Givei. the linear model used in this problem
ii. the estimated regression equation.
(c) Describe the results of the significance test for the slope.Give the hypotheses beingtested, the test statistic with degrees of freedom, thep-value, and your conclusion insentence form.