A parallelepiped block, suspended by a cable that passes through a pulley $($see figure below$),$ keeps a tank with water closed up to a height h $=1$ m$,$ by ensuring contact between the gate AB and the stop. The block has a square base and height h$1=1\mathrm{.}5$ m$,$ being composed of a material with mass specifies $=2000/3.$ The gate has height h$2=2$ m and width b $=3$ m$.$ Determine the minimum width of the block base $($L$)$ to ensure the tank closes. Given: $=30,=0\mathrm{.}2$