Which of the following compounds are formed when boron trichloride is treated with water?

Consider the following statements for diborane $(B_2H_6)$:
$1.$ Boron is approximately $sp^3$ hybridized.
$2.$ $B-H-B$ angle is $180^{\circ}$.
$3.$ There are two terminal $B-H$ bonds for each boron atom.
$4.$ There are only $12$ bonding electrons available.
Which of these statements are correct?

The stability of $+1$ oxidation state among $Al$,$Ga$,$In$ and $Tl$ increases in the sequence:

Boric acid,$H_3BO_3$,is a/an ....

Given below are two statements:
Statement $I$: Aluminium is more electropositive than thallium as the standard electrode potential value of $E^\circ_{Al^{3+}/Al}$ is negative and $E^\circ_{Tl^{3+}/Tl}$ is positive.
Statement $II$: The sum of first three ionization enthalpies of boron is very high when compared to that of aluminium. Due to this reason, boron forms covalent compounds only and aluminium forms $Al^{3+}$ ion.

Which of the following on hydrolysis produces diborane $(B_2H_6)$?