\[\boxed{\mathbf{797\ (797)}.\ Еуроки\ - \ ДЗ\ без\ мороки}\]
\[\boxed{\ \mathbf{797}\mathbf{\ (621)}.\ Еуроки\ - \ ДЗ\ без\ мороки}\]
\[a = 10\ дм,\ \ \ b = 8\ дм,\ \ \ c = 4\ дм\]
\[V = abc = 10 \cdot 8 \cdot 4 = 320\ дм^{3}.\]
\[Ответ:320\ дм^{3}.\]