Problem $2(4$ questions, $6$ points each, Total $24$ points$)$

Predict which one of each pair below will have the lower boiling point temperature. Justify your prediction in each case $(5$ points each for explanation$).$

Neohexane and Isohexane

Methylcyclopentane and Isopropylbenzene $($Cumene$)$

$2-$Methylpentane $($Isohexane$)$ and $2,2-$ Dimethylbutane $($Neohexane$)$

Toluene and n$-$Butylbenzene