8. (3 points) For any two numbers $x, y$, define a new operation * as: $\mathrm{x} * \mathrm{y}=\frac{\mathrm{x} \times \mathrm{y}}{\mathrm{m} \times \mathrm{x}+2 \times \mathrm{y}}$ (where $m$ is a fixed number). If $1 * 2=\frac{2}{5}$, then $m=$ $\qquad$ , $2 * 6=$ $\qquad$ .
【Solution】Solution: (1) $1 * 2=\frac{1 \times 2}{\mathrm{~m} \times 1+2 \times 2}=\frac{2}{5}$,
that is $2 m+8=10$,
$$
\begin{aligned}
2 m & =10-8, \\
2 m & =2, \\
m & =1,
\end{aligned}
$$
$$
\begin{aligned}
& \text { (2) } 2 * 6, \\
= & \frac{2 \times 6}{2 \times 1+2 \times 6}, \\
= & \frac{6}{7},
\end{aligned}
$$

Therefore, the answers are: $1, \frac{6}{7}$.