2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/70702We show that the transience or recurrence of a random walk in certain random environments on an arbitrary infinite locally finite tree is determined by the branching number of the tree, which is a measure of the average number of branches per vertex. This generalizes and unifies previous work of the authors. It also shows that the point of phase transition for edge-reinforced random walk is likewise determined by the branching number of the tree. Finally, we show that the branching number determines the rate of first-passage percolation on trees, also known as the first-birth problem. Our techniques depend on quasi-Bernoulli percolation and large deviation results.11 pagesProbability60J15, 60K35 (Primary) 82A43 (Secondary)Random Walk in a Random Environment and First-Passage Percolation on Treestext