SELECT name ,  max(revenue) ,  Headquarter FROM manufacturers GROUP BY Headquarter
What are the names and revenues of the companies with the highest revenues in each headquarter city?
[Schema (values) (types)]: | manufactory_1 |  Manufacturers : code (text) , name (number) , headquarter (text) , founder (text) , revenue (text) | Products : code (text) , name (number) , price (text) , manufacturer (text);