Constitutional isomers

Question

Are the following constitutional isomers?

C-C-C-C-F C-C-C-C-F C-C-C-C-F C-C-C-C-F

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C C C C

(all carbons are understood to be attached to hydrogens to satisfy octet rule)

Answer 1

These are positional isomers which are a type of constitutional isomer. The others have to do with different branching (like isopropane and butane) and different functional groups.(like an alcohol and an ether)