2. As part of the same project described above, the researchers investigated how serum PFOA levels (in ng/ml) are associated with age in years.The subjects in the study ranged in age from 42 years to 51 years. A linear model was fit to the data and the output is given below.

Coefficients:  Estimate Std. Error t value Pr(>|t|) (Intercept) 4.35724 2.94601 1.479 0.142512 age 0.21704 0.06363 3.411 0.000959 *** Residual standard error: 1.551 on 93 degrees of freedom Multiple R-squared: 0.1112, Adjusted R-squared: 0.1016 F-statistic: 11.64 on 1 and 93 DF, p-value: 0.000959 

a.Perform a Hypothesis test to test the effect of age on PFOA levels, Give Ho, Ha, value of the test-statistic, distribution (and df) of test statistic if Ho is true, p-value and conclusions. Be sure to address significance, magnitude and direction in the conclusions

b.What proportion of variability in PFOA levels is explained by the model?

Would you interpret the intercept in this study? Why or why not?