\[\boxed{\mathbf{1}\mathbf{.140}}\]
\[\textbf{а)}\ 17 + 15 = 32\]
\[39 + 14 = 53\]
\[57 + 43 = 100\]
\[46 + 0 = 46\]
\[\textbf{б)}\ 23 - 17 = 6\]
\[42 - 16 = 26\]
\[81 - 46 = 35\]
\[72 - 53 = 19\]
\[\textbf{в)}\ 12 \cdot 5 = 60\]
\[39 \cdot 2 = 78\]
\[14 \cdot 0 = 0\]
\[83 \cdot 1 = 83\]
\[\textbf{г)}\ 360\ :6 = 60\]
\[450\ :5 = 90\]
\[560\ :8 = 70\]
\[111\ :1 = 111\]