In the borax bead test,which of the following compounds is formed?

Boric acid is polymeric due to

Which of the following statements is correct regarding boron hydrides?

Identify the correct statements:
$i$. Oxidation of $NaBH_4$ with $I_2$ gives $B_2H_6$
$ii$. $B_2H_6$ burns in oxygen and releases an enormous amount of energy
$iii$. $B_2H_6$ on hydrolysis gives a tribasic acid

What happens when:
$(a)$ Borax is heated strongly,
$(b)$ Boric acid is added to water,
$(c)$ Aluminium is treated with dilute $NaOH$,
$(d)$ $BF_{3}$ is reacted with ammonia?

Give the chemical reaction for the preparation of a borax bead.