  We present measurements of the linear polarization amplitudes and the strong
relative phases that describe the flavor-untagged decays $B_{d}^{0}\to J/\psi
K^{*0}$ and $B_{s}^{0}\to J/\psi\phi$ in the transversity basis. We also
measure the mean lifetime $\bar{\tau}_{s}$ of the $B_{s}^{0}$ mass eigenstates
and the lifetime ratio $\bar{\tau}_{s}/\tau_{d}$. The analyses are based on
approximately 2.8 fb$^{-1}$ of data recorded with the D0 detector. From our
measurements of the angular parameters we conclude that there is no evidence
for a deviation from flavor SU(3) symmetry for these decays and that the
factorization assumption is not valid for the $B_{d}^{0}\to J/\psi K^{*0}$
decay.
