Consider the multiple linear regression model \[ y=\beta_{0}+\beta_{1} x_{1}+\beta_{2} x_{2}+\beta_{3} x_{3}+\beta_{4} x_{4}+\varepsilon \] Using the procedure for testing a general linear hypothesis, show how to test

a. $H_{0}: \beta_{1}=\beta_{2}=\beta_{3}=\beta_{4}=\beta$

b. $H_{0}: \beta_{1}=\beta_{2}, \beta_{3}=\beta_{4}$

c. $H_{0}: \beta_{1}-2 \beta_{2}=4 \beta_{3}$ 

$\beta_{1}+2 \beta_{2}=0$