$M+CuSO_4\rightarrow MSO_4+Cu\downarrow$$x x$
$M+Pb(NO_3)_2\rightarrow M(NO_3)_2+Pb\downarrow$
$x x$
$\Rightarrow \begin{cases}\frac{x(M-64)}{m}=\frac{0,05}{100} \\\frac{x(207-M)}{m}=\frac{7,1}{100} \end{cases}\Rightarrow \frac{207-M}{M-64}=\frac{7,1}{0,05}\Rightarrow M=65\Rightarrow M:Zn$