Which metal ion gives a violet bead in the borax bead test?

Assign $A, B, C, D$ from the given type of reaction.
$MCrO_4 \downarrow (M^{2+} = Ba^{2+}, Pb^{2+}) + AcOH \longrightarrow$ No dissolution

Which of the following salts does not give a borax bead test?

The salt used for performing the 'bead' test in qualitative inorganic analysis is

When sodium chloride is heated with concentrated $H_2SO_4$ and solid potassium dichromate,which compound containing $Cr$ in the $+6$ oxidation state is formed as a gas?

Which salt is used during the bead test in the qualitative analysis of inorganic substances?