Draw the structure of the following:

$2-$phenylbutane.

Draw the structure of the following:

$5-\text{chloro}-3-\text{ethyl}-1,2-\text{dimethylnaphthalene}$

Draw the structure of the following:

$2,3-\text{dimethyl}-5-\text{phenyl}-1,3,5-\text{octatriene}$

Draw the structure of the following:

$2,3-$dichlorotoluene.

Draw the structure of the following:

$1,2-$diethylbenzene

Draw the structure of the following:

$2, 7-$dimethylnaphthalene

Draw the structure of the following:

Styrene.

Draw the structure of the following:

$1,2-$dimethylbutylbenzene.