Boron and silicon of very high purity can be obtained through :

The final major product of the following reaction is :

Among the following compounds, geometrical isomerism is exhibited by :

If
$$\int {{{\cos \theta } \over {5 + 7\sin \theta - 2{{\cos }^2}\theta }}} d\theta $$ = A$${\log _e}\left| {B\left( \theta \right)} \right| + C$$,

where C is a constant of integration, then $${{{B\left( \theta \right)} \over A}}$$
can be :