Inorganic benzene reacts with $HCl$ to form a compound $B_3N_3H_9Cl_3$. The protonation occurs at

Match the following compounds in List-$I$ with their properties/names in List-$II$.

List-$I$ (Compound)	List-$II$ (Property/Name/Structure)
$A$. $H_3BO_3$	$1$. Dimeric form
$B$. $AlCl_3$	$2$. Back bonding
$C$. $B_3N_3H_6$	$3$. Hydrogen bonding
$D$. $BF_3$	$4$. Inorganic benzene

Identify the correct statements from the following :
$I$. $Ga_2O_3$ is an amphoteric oxide.
$II$. The dimer of aluminium chloride has three $Al-Cl-Al$ bridge bonds.
$III$. Boron is a very hard refractory solid of high melting temperature.

Explain the following:
$(1)$ Gallium has higher ionisation enthalpy than aluminum.
$(2)$ Boron does not exist as $B^{3+}$ ion.

Select the correct statements for diborane $(B_2H_6)$:
$1.$ Boron is approximately $sp^3$ hybridized.
$2.$ The $H-B-H$ bridge angle is $180^o$.
$3.$ There are two terminal $B-H$ bonds for each boron atom.
$4.$ There are only $12$ bonding electrons available.

Aluminium $(III)$ chloride forms a dimer because ........