Give the structure of the following:
$(i)$ $4-(1, 1-$dimethylpropyl$)-3-$ethyl$-4, 7-$dimethyldecane
$(ii)$ $5-(1-$methylbutyl$)-7-(2-$methylbutyl$)$undecane

(N/A) The structures are drawn based on the $IUPAC$ nomenclature rules:
$(i)$ The parent chain is decane ($10$ carbons). At position $3$,there is an ethyl group. At position $4$,there is a $1, 1-$dimethylpropyl group. At positions $4$ and $7$,there are methyl groups.
$(ii)$ The parent chain is undecane ($11$ carbons). At position $5$,there is a $1-$methylbutyl group. At position $7$,there is a $2-$methylbutyl group.