Return on investment $($ROI$)$ could be calculated using which of the following formulas?

Multiple Choice

Margin $\backslash$times $($Net operating income $-$: Sales$)$

Margin $\backslash$times $($Sales $-$: Net operating income$)$

Margin $\backslash$times $($Average operating assets $-$: Sales$)$

Margin $\backslash$times $($Sales $-$: Average operating assets$)$