Copper nitrate
Copper nitrate is the oxidizing agent as it gets reduced from +2 to 0 oxidization State and oxidize Fe from 0 to +2 state.
I think the answer is 1s²2s²2p⁶. Since neon has an atomic number of 10, we know that it needs to have 10 electrons and since it is in the second row it cannot have any d electrons which makes the first option incorrect. The second option is incorrect because the 2s⁴ can't exist since s orbitals can only hold 2 electrons. The fourth option cannot be right because it again neon cannot have d electrons due to it being in the second row.
I hope this helps. Let me know if anything is unclear.
Nitrogen, Oxygen, and Fluorine do not follow this trend. The noble gas electron configuration will be close to zero because they will not easily gain electrons.
I think its mass of volume
