Using the bonding model for a semiconductor, indicate how one visualizes

i) No carriers
a) Negatively charged ions
b) Empty energy bands
c) Positively charged ions
d) Neutral atoms

ii) An electron
a) In a filled valence band
b) In a partially filled conduction band
c) Attached to a nucleus
d) In the outermost electron shell

iii) A donor
a) Negatively charged ions
b) In a fully filled valence band
c) Positively charged ions
d) In a partially filled conduction band