Screenshot very easy

1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d⁶

Explanation:

Iron is soft, bright white metal.

Its symbol is Fe, atomic number is 26 and atomic mass is 55.85 amu.

It is present in group 8 of periodic table.

It is used to make the steel.

It is malleable and ductile used to make the sheets.

It is good conductor of heat and electricity because of moveable electrons that can easily move from one to another atom.

Its density is 7.87 g/cm³.

Electronic configuration:

Fe₂₃ = 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d⁶

Abbreviated electronic configuration:

Fe₂₃ = [Ar] 3d⁶4s²

c) should be the answer.