GOB Chemistry
It is correctly named because it takes into account the correct prefix and position of the substituents, as well as the correct name of the parent chain.
It is incorrectly named because it provided the wrong prefix and position of the substituent. Its correct name is 2-methylhexane.
It is incorrectly named because it provided the wrong name of the parent chain and the wrong prefix of the substituent. Its correct name is 1,1-methylheptane.
It is incorrectly named because it provided the wrong name of the parent chain and the wrong position of the substituent. Its correct name is 2-methylheptane.