\[\boxed{\mathbf{41.\ }еуроки - ответы\ на\ пятёрку}\]
\[a = 5b;\ \ \ P = 96\ см:\]
\[P = 2a + 2b = 96\]
\[2a + 2b = 96\]
\[a + b = 48\]
\[5b + b = 48\]
\[6b = 48\]
\[b = \frac{48}{6} = 8.\]
\[a = 5 \bullet 8 = 40.\]
\[Ответ:\ \ 40\ см;\ 8\ см.\]