Factorization and color-suppression in hadronic b --> d$^{(*}$)n$\pi$ decays

The factorization hypothesis and color-suppression are investigated by analyzing the largest, to date, sample of B mesons. In all, 20 hadronic two-body decay modes are reconstructed using 2.04 fb^-1 of data collected with the CLEOII detector. We measure the branching fraction of five class I and five class III decay modes and set upper limits on branching fractions of ten class II decays. The branching fraction measurements are used to determine the BSW parameters a_1, and a_2/a_1. In addition, we measure the fraction of B-> D^{*+} rho^- decays which decay longitudinally polarized. The results are found to be consistent with factorization and color-suppression