Given the matrix below, how many total shipments are made from Chicago? \begin{tabular}{|l|r|r|r|r|} \hline St. Louis & 144 & 775 & 44 & 963 \\ \hline Chicago & 992 & 345 & 458 & 1795 \\ \hline Demand & 1269 & 1143 & 600 & 3012\3012 \\ \hline \end{tabular} \begin{tabular}{|l|r|r|r|r|} \hline & & & & \\ \hline Shipments & \multicolumn{1}{|c|}{ Denver } & Yuma & Miami & Row Total \\ \hline Houston & & 400 & & 400 \\ \hline St. Louis & 150 & & 100 & 250 \\ \hline Chicago & & 50 & 600 & 650 \\ \hline Column Total & 150 & 450 & 700 & 1300\1300 \\ \hline \end{tabular} \begin{tabular}{|l|l|} \hline Total Cost & $327,250 \\ \hline \end{tabular}