Please answer both questions and label each individual carbon please. For the first one, I get 8 carbons on the left molecule vs 7 carbons on the right molecule. Why are they constitutional isomers if they have different number of carbons?

Also, for the second question, please label all carbons and explain why if they both have 5 carbons and one F they are unrelated molecules? Thank you.

Constitutional Isomers: For euch pair of molecules below, state whether the molecules are constitutional isomers, the same molecule, or neither. vs A. Constitutional Isomers B. Same Molecule C. Unrelated Molecules (Not Isomers) Vs A. Constitutional Isomers B. Same Molecule C. Unrelated Molecules (Not Isomers)