For each of the six independent situations that follow, compute the missing amounts: a. Using contribution marpin per unit: \begin{tabular}{|c|c|c|c|c|c|c|} \hline & 5ales & Variable Costs & Contribution Margin per Unit & Fixed Costs & Operating Income & Units Sold \\ \hline \multirow{2}{*}{ (1) } & s & \multirow{2}{*}{$120,000} & \multirow{2}{*}{$20} & \multirow{2}{*}{ \$ 55,000} & \multirow{2}{*}{$25,000} & \multirow{2}{*}{4,000} \\ \hline & 200,000 & & & & & \\ \hline (2) & 180,000 & 105,000 & 15 & 45,000 & 30,000 & 5,000 \\ \hline (3) & 800,000 & 360,000 & 30 & 150,000 & 90,000 & 8,000 \\ \hline \end{tabular} b. Using the contribution margin ratio