In diborane $(B_2H_6)$, the number of electrons that accounts for bonding in the bridges is

The number of neutrons present in the more abundant isotope of boron is $x$. Amorphous boron upon heating with air forms a product,in which the oxidation state of boron is $y$. The value of $x+y$ is ...

The incorrect statement from the following for borazine is:

Chemically,borax is:

Statement $I$: Boron does not exhibit allotropy.
Statement $II$: Boron is an extremely hard and black-coloured solid.

What is the formula for meta-boric acid?