$\frac{W}{m^2}*K.$ The time it takes for the surface temperature of the plates to drop to $120C$ is

$.($Solve this problem using an appropriate software.$)$

Multiple Choice

$0\mathrm{.}66$

$0\mathrm{.}8$

$2\mathrm{.}6$

$3\mathrm{.}2$

$1\mathrm{.}4$