Answer:
1) 3-Ethylanisole
2) 2,3-Dibromobenzoic acid
3) 3-Fluorotoluene
Explanation:
Let us try to look at the structures of each compound one after the other as described in the question.
1) A ring with six vertices and alternating double and single bonds must refer to a benzene ring. A benzene ring having -OCH3 attached to the first vertex is called anisole. If a -CH2CH3 group is now attached at position 3, we now name the compound 3-Ethylanisole.
2) A ring with six vertices and alternating single and double bonds is a benzene ring. If the ring has -COOH attached to the first vertex, we call it benzoic acid. If bromine atoms are attached to the second and third vertices respectively, the compound is now named 2,3-Dibromobenzoic acid.
3) A ring with alternating single and double bonds is a benzene ring. If a -CH3 group is attached to the first vertex, we call the compound toluene. If a fluorine atom is now attached to position 3, the compound can now be named 3-Fluorotoluene