Consider a cubic block with an edge of $50$ cm$,$ isolated on all faces, except two opposite ones. block is initially at $25\backslash$deg C$.$ Suddenly, both non$-$insulated sides are subjected to a thermal process, remaining at a constant temperature of $500\backslash$deg C$.$ Determine the temperature $5$ cm from the surface, $40$ minutes after the disturbance. Additinal data: density of block: $6780$ kg$/$m$3$; k$($block$)=56$W$/$m$.$k; alpha$($block$)=7\mathrm{.}26*10$power$(-6)$m$2/$s