§ Задание 13
\[\boxed{\mathbf{13.}}\]
\[2 \cdot 7 = 14\]
\[2 \cdot 8 = 16\]
\[3 \cdot 5 = 15\]
\[3 \cdot 6 = 18\]
\[4 \cdot 4 = 16\]
\[4 \cdot 5 = 20\]
\[\boxed{\mathbf{13.}}\]
\[2 \cdot 7 = 14\]
\[2 \cdot 8 = 16\]
\[3 \cdot 5 = 15\]
\[3 \cdot 6 = 18\]
\[4 \cdot 4 = 16\]
\[4 \cdot 5 = 20\]