The kinematic viscosity of a certain solvent system depends on the ratio of the two solvents and the temperature. Table B. 10 summarizes a set of experimental results.

a. Fit a multiple linear regression model relating the viscosity to the two regressors.

b. Test for significance of regression. What conclusions can you draw?

c. Use $t$ tests to assess the contribution of each regressor to the model. Discuss your findings.

d. Calculate $R^{2}$ and $R_{\text {Adj }}^{2}$ for this model. Compare these values to the $R^{2}$ and $R_{\text {Adj }}^{2}$ for the simple linear regression model relating the viscosity to temperature only. Discuss your results.

e. Find a $99 % \mathrm{CI}$ for the regression coefficient for temperature for both models in part d. Discuss any differences.

x2 y 0.9189 0.9189 -10 3.128 0 2.427 0.9189 10 1.94 0.9189 20 1.586 0.9189 30 1.325 0.9189 40 1.126 0.9189 50 0.9694 0.9189 60 0.8473 0.9189 70 0.7481 0.9189 80 0.6671 0.7547 -10 2.27 0.7547 0 1.819 0.7547 10 1.489 0.7547 20 1.246 0.7547 30 1.062 0.7547 40 0.916 0.7547 50 0.8005 0.7547 60 0.7091 0.7547 70 0.6345 0.7547 80 0.5715 0.5685 -10 1.593 0.5685 0 1.324 0.5685 10 1.118 0.5685 20 0.9576 0.5685 30 0.8302 0.5685 40 0.7282 0.5685 0.647 0.5685 0.5784 0.5685 0.5219 0.5685 0.4735 0.361 1.161 0.361 0 0.9925 0.361 0.361 0.361 0.361 0.361 0.361 0.361 0.361 80 9884878 10 0.8601 20 0.7523 30 0.6663 0.594 50 0.5338 60 0.4804 70 0.4361 0.4016