Theorem: Set A = A<sub>1</sub>, A<sub>2</sub>, A<sub>3</sub>,..., A<sub>m</sub> have a system of distinct representatives iff for all subset I ? {1,2,3,...,m}. We know set A is a transversal, and they are all distinct such that x<sub>i</sub> ? A<sub>i</sub> Show that theorem above equivalent to Hall's condition using defined bipartite graph. Please do it by detail.