3 questions, Please help me here kinda out on a limb since I was absent when this was discussed

Write the oxidation number of the underlined ion.
Fe0 =
(Wrong answers: +2 and +3)

Write the oxidation number of the underlined ion.
KM04 =
(Wrong answers: +7 and -8)

Write the oxidation number of the underlined ion.
A1203 =
(Wrong answers: +3 and -2)