query question - where clause with a max involved

I hope you can deduce what i am asking from the excel spreadsheet
it has 3 tables listed and the desired results.  I don't know how to write this query.

the problem area is the gallons table.  
 
please refer to spreadsheet.  
it has to do with selecting row data from a max value where the max value is not known.  and then a 2nd max also
experts-exchange.xlsx