8. Fill the circles in the figure with the numbers $2, 4, 6, 8, 10, 12, 14$ so that the sum of the three numbers in each row is equal. What is this equal sum? $\qquad$ (Write down all possible answers.)
【Analysis】 $3 A=56+2 X, X=2,8,14 \Rightarrow A=20,24,28$. Examples omitted.