$8\mathrm{.}4$ Polymerization of styrene by sodium naphthalene was performed at $35C$ in dioxane. From the residual

monomer and average degree of polymerization of the polymer formed in accurately measured reaction

time the following data were obtained for two different monomer $($M$)-$ initiator $($CA$)$ compositions :

Calculate the overall rate constant and the total concentration of chain centers corresponding to the two

initiator concentrations.