The annual report of Dennis Industries cited these primary earnings per common share for the past $5$ years: $$2\mathrm{.}46,$ $$1\mathrm{.}07,$ $$2\mathrm{.}10,$ $$4\mathrm{.}22,$ and $$7\mathrm{.}72.$ If we assume these are population values.

a$.$ What is the arithmetic mean primary earnings per share of common stock? $($Round your answer to $2$ decimal places.$)$

b$.$ What is the variance? $($Do not round intermediate calculations. Round your answer to $2$ decimal places.$)$