CREATE TABLE table_39146 ("Date" TEXT, "Race" TEXT, "Distance" TEXT, "Venue" TEXT, "Radio" TEXT)

What is the venue of the napa auto parts 200 race with a mrn radio?
SELECT "Venue" FROM table_39146 WHERE "Radio" = 'mrn' AND "Race" = 'napa auto parts 200'
SELECT "Venue" FROM "table_39146" WHERE "Race" = 'napa auto parts 200' AND "Radio" = 'mrn'