1. Suppose we have a transportation problem with 3 sources and 5 destinations. Each destination can be reached from each source, each source has a given capacity, and each destination has a given demand. Ignoring nonnegativity, how many constraints are needed in this problem? 5 15 8 3

2. In order to model a maximum flow problem with linear programming, we require that

		the number of edges entering a node is equal to the number of edges leaving the node.
		the decision variables are equal to 1 if an edge is used and 0 if it is not used.
		there is exactly one edge entering each node.
		the amount of flow entering a node is equal to the amount of flow leaving the node.