Verified answer

1. Does the hexagon have a circle in the middle?

If it does it is a benzene ring and the compounds IUPAC name is

methyl benzene

You don't need to specify the position of the substituent because there is only one

It's common name is toluene

If the hexagon does not have a circle in the middle then it is a cyclohexane

since it has a CH3 substituent it will be

methyl cyclohexane

2.

There are 6 carbons in the main chain, thus it is a hexane

you have 2 methyl substituents on carbon 2 (2,2-dimethyl)

and 1 ethyl substituent on carbon 4 (4-ethyl)

when you construct the name list the substituents alphabetically, the prefix to the methyls is not included when assigning alphabetical position (ie ignore the di, dimethyl is assigned based on the m of methyl)

4-ethyl-2,2-dimethylhexane