Which compound among the following has the highest dipole moment?

How many among the given species have a bond order of 0.5 ?

$$\mathrm{H}_2^{+}, \mathrm{He}_2^{+}, \mathrm{He}_2^{-}, \mathrm{B}_2^{+}, \mathrm{F}_2^{-}, \mathrm{Be}_2^{2-}$$

Match the following.

The structure of diborane B$$_2$$H$$_6$$ is given below. Identify the bond angles of x and y. In diborane, ........... are commonly known as banana-bonds.