5.16 Consider a variation of the consensus problem in which the validity condition is the following: There must be at least one admissible execution with decision value 0, and there must be at least one admissible execution with decision value 1. Prove that there is no wait-free algorithm for this problem in an asynchronous system. Hint: Modify the the proof of the existence of a bivalent initial configuration (Lemma 5.16).