CREATE TABLE table_204_210 (id DECIMAL, "rnd" DECIMAL, "circuit" TEXT, "lmp1 winning team\ lmp1 winning drivers" TEXT, "lmp2 winning team\ lmp2 winning drivers" TEXT, "gt1 winning team\ gt1 winning drivers" TEXT, "gt2 winning team\ gt2 winning drivers" TEXT, "results" TEXT)

what is the total number of circuits listed on the chart ?
SELECT COUNT(DISTINCT "circuit") FROM table_204_210
SELECT COUNT(DISTINCT "circuit") FROM "table_204_210"