CREATE TABLE table_203_339 (id DECIMAL, "year" TEXT, "car" DECIMAL, "start" DECIMAL, "qual" DECIMAL, "rank" DECIMAL, "finish" DECIMAL, "laps" DECIMAL, "led" DECIMAL, "retired" TEXT)

what car achieved the highest qual ?
SELECT "car" FROM table_203_339 ORDER BY "qual" DESC LIMIT 1
SELECT "car" FROM "table_203_339" ORDER BY "qual" DESC NULLS LAST LIMIT 1