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_49524 ( "Year" text, "Designated Grand Prix" text, "Track" text, "250 cc" text, "350 cc" text, "500 cc" text, "Report" text )

### Question ###
What year did Freddie Frith win the 350cc and Enrico Lorenzetti win the 500cc?

### Accurate SQL ###

SELECT "Year" FROM table_49524 WHERE "350 cc" = 'freddie frith' AND "500 cc" = 'enrico lorenzetti'