In a multiple regression analysis involving 20 observations and 5 independent variables, the total variation $SST=250$ and $SSE=35$. The multiple coefficient of determination adjusted for degrees of freedom is:
A. 0.835
B. 0.831
C. 0.810
D. 0.860

In a multiple regression analysis involving 40 observations and 5 independent variables, the total variation $SST=350$ and $SSE=50$. The multiple coefficient of determination is:
A. 0.8571
B. 0.8529
C. 0.8408
D. 0.8469