Answer
A. hexane
B. 2,3-methyloctane
C. 2,3-methylpentane
Work Step by Step
A. The entire structure is a parent strand with 6 carbon atoms.
B. The longest parent strand has 8 carbons total. 2 substituents exist at the 2nd and 3rd carbon.
C. The longest parent strand has 5 carbons, hence pentane. 2 substituents exist, at the 2nd and 3rd carbon atom of the parent strand.