\[\boxed{\mathbf{1}\mathbf{.104}}\]
\[\textbf{а)}\ 320\ :8 = 32\ :8 \cdot 10 =\]
\[= 4 \cdot 10 = 40\]
\[\textbf{б)}\ 1326\ :13 =\]
\[= (1300 + 26)\ :13 =\]
\[= 1300\ :13 + 26\ :13 =\]
\[= 100 + 2 = 102\]
\[\textbf{в)}\ 400 \cdot 7 = 4 \cdot 7 \cdot 100 =\]
\[= 28 \cdot 100 = 2800\]
\[\textbf{г)}\ 602 \cdot 6 = (600 + 2) \cdot 6 =\]
\[= 600 \cdot 6 + 2 \cdot 6 = 3600 + 12 =\]
\[= 3612\]