Below is the list of tables from the database along with their columns and datatype. Need to generate an accurate SQL query for the question.
Only use the columns present in the respective table. Only use the columns which are required to generate the SQL query. Only use table joins if required and not otherwise.

### Tables ###
TABLE: CREATE TABLE table_2889810_2 ( moto2_250cc VARCHAR, country VARCHAR )

### Question ###
how many total number of moto2/250cc when country is united states

### Accurate SQL ###

SELECT COUNT(moto2_250cc) FROM table_2889810_2 WHERE country = "United States"