Solve for the missing amounts for the following separate cases.

\begin{tabular}{|c|c|r|r|r|r|} \hline Case & Salespriceperunit & Variablecostsperunit & \multicolumn{2}{c|}{Contributionmarginperunit} & Contributionmarginratio \\ \hline 1 & $10 & $ & 8 & & \\ \hline 2 & & & 45 & 54 & \\ \hline 3 & & & & & \\ \hline \end{tabular}