$16.$ A rental car company has an imbalance of cars at seven of its locations. The following net$-$ work shows the locations of concern $($the nodes$)$ and the cost to move a car between loca$-$ tions. A positive number by a node indicates an excess supply at the node, and a negative number indicates an excess demand. $+530227304520157+6255+2282520123635+3$ Develop a linear programming model of this problem. b$.$ Solve the model formulated in part $($a$)$ to determine how the cars should be redistrib$-$ uted among the locations