The ${?}^{1}H-NMR$ spectrum of Polystyrene, synthesized by reverse iodine transfer polymerization method, is given below. The table gives chemical shift $()$ and integration values of the corresponding peaks. Calculate the molecular weight of this polymer.

$\backslash$table$[[\frac{}{p}pm,0\mathrm{.}9,1\mathrm{.}3,1\mathrm{.}7,4\mathrm{.}5,6\mathrm{.}5-7\mathrm{.}5$