Light Me Up Lamps has variable expenses of $50\%$ of sales and monthly fixed expenses of $$50,000.$ The monthly target operating income is $$70,000.$ What is Light Me Up Lamps' operating leverage factor at the target level of operating income?

A$.0\mathrm{.}58$

B$.0\mathrm{.}71$

C$.2\mathrm{.}4$

D$.1\mathrm{.}71$