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Problem 1: Let G be a graph that has a nowhere-zero 4-flow. Suppose G−e is bridgeless. Prove that G−e has a nowhere-zero 5-flow.
Problem 2: Let G1 be a graph with a nowhere-zero k1-flow and let G2 be a graph with a nowhere-zero k2-flow. Prove that the G1∪G2 has a nowhere-zero k1k2-flow.