The activation energy for hole formation in Si is given as $3\mathrm{.}6$eV$.$ Calculate the hole density per cm$^3$ in Si at $1050$deg C$.$ At this temperature, the density of Si is given as $233$ g cm$^-3$ and Mer as $28\mathrm{.}09$ g mol$^-1.($Density should not change with temperature$)$