This is written by Hluf Negash which studies the decays of B-meson in the framework of Bethe-Salpeter equation under covariant instantaneous ansatz. The analysis of this study gives important information about the internal structure of hadrons. The prediction of the properties of strongly interacting particles using the mesonic and baryonic sectors is of great importance since these hadrons can be easily produced in experiments and hence the theoretical predictions can be verified.