Provide the proper IUPAC name for the compound below.

trans$-1-$tert$-$butyl$-4-$ethylcyclohexane

cis$-1-$tert$-$butyl$-4-$ethylcyclohexane

trans$-1-$isopentyl$-4-$ethylcyclohexane

$1-$tert$-$butyl cyclohexane

trans$-1-$methyl$-4-$ethylcyclohexane