Consider a flow network G = (V, E, c, l, d) given to the problem of circulation with demands and lower bounds discussed in the textbook section in pages 382-384. Here, V is the set of nodes, E is the set of edges, c(e) and l(e) are, respectively, the upper bound and the lower bound of flow on an edge e E, and d(v) is the demand at a node d V. Read the section and (a) briefly summarize the key idea for solving the circulation with demands and lower bounds problem by reducing (i.e., reformulating) it to the circulation with demands problem (discussed in the textbook section in pages 379-382), and (b) give a sketch of the reduction algorithm that constructs a flow network G = (V, E, c, d) from G = (V, E, c, l, d) and give the reduction algorithms runtime complexity with an explanation assuming an adjacency list representation of the graph (V, E). Note that G has no lower bounds on its edges.