In a multiple regression analysis involving $k$ independent variables and $n$ data points, the degrees of freedom associated with the SSE is:
A. $n-1$
B. $n-k$
C. $n-k-1$
D. $k-1$

A multiple regression model involves 10 independent variables and 30 observations. If we want to test at the 5% significance level the parameter $\beta_4$, the critical value will be:
A. 2.093
B. 1.729
C. 1.697
D. 2.228