Which group of the periodic table contains only metals?

Which of the following orders is correct $-$

If the valence shell electronic configuration for an element is $ns^2 np^5$,this element will belong to the group of

The set of amphoteric oxides among $ZnO$,$Tl_2O_3$,$In_2O_3$,$B_2O_3$,$PbO$,$SnO_2$ is

What are the major differences between metals and non-metals?

The electronic configuration of three elements $A, B$ and $C$ are given below. The molecular formula of the compound formed from $B$ and $C$ will be
$A : 1s^2, 2s^2, 2p^6$
$B : 1s^2, 2s^2, 2p^6, 3s^2, 3p^3$
$C : 1s^2, 2s^2, 2p^6, 3s^2, 3p^5$