\[\boxed{\text{349.}}\]
\[\textbf{а)}\ \frac{2}{11} = \frac{2 \cdot 11}{11 \cdot 11} = \frac{22}{121}\ \]
\[\textbf{б)}\ \frac{5m}{8} = \frac{5m \cdot 8}{8 \cdot 8} = \frac{40m}{64}\ \]
\[\textbf{в)}\ \frac{8}{a} = \frac{8 \cdot 3}{a \cdot 3} = \frac{24}{3a}\ \]
\[\textbf{г)}\ \frac{5a}{7c} = \frac{5a \cdot 13}{7c \cdot 13} = \frac{65a}{91c}\]