Place the compounds, LiF, N2, NH2CH3, in order of increasing boiling point.
a) NH2CH3 < N2 < LiF
b) N2 < NH2CH3 < LiF
c) N2 < LiF < NH2CH3
d) NH2CH3 < LiF < N2
e) LiF < NH2CH3 < N2