2. Who is the strongest on dragon ball z? Goku is the strongest and he proved that he was the strongest by defeating everyone he challenged.
3. Why did android 18 fall in love with a human being when she was built to have no feelings? Because she has been rescued by a very nice guy who fell in love with the robot and turned her into a human being.
4. Did goku defeat the legendary super saiyen? Yes he did defeat brolly the legendary super saiyen by the super kamehameha by goku and his son.