\[\boxed{\text{4.\ 269}}\]
\[\textbf{а)} - 4 \cdot 8 = - 32\]
\[\textbf{б)}\ 7 \cdot ( - 9) = - 63\]
\[\textbf{в)} - 20 \cdot 15 = - 300\]
\[\textbf{г)} - 238 \cdot 0 = 0\]
\[\textbf{д)} - 1 \cdot 423 = - 423\]
\[\textbf{е)}\ 0 \cdot ( - 1) = 0\]