user: Question: how many total number of moto2/250cc when country is United States
Columns: ['Country', 'MotoGP/500cc', '350cc', 'Moto2/250cc', 'Moto3/125cc', '80cc/50cc', 'Total']
Types: ['text', 'real', 'real', 'real', 'real', 'real', 'real']
Sample row: ['Italy', 20.0, 8.0, 22.0, 23.0, 2.0, 75.0]
SQL:

assistant: SELECT SUM("Moto2/250cc") FROM "Table" WHERE "Country" = 'United States';