CREATE TABLE table_79703 ("Rank" FLOAT, "Lane" FLOAT, "Athlete" TEXT, "Nationality" TEXT, "Time" FLOAT, "React" FLOAT)

What's Brazil's lane with a time less than 21.15?
SELECT MIN("Lane") FROM table_79703 WHERE "Nationality" = 'brazil' AND "Time" < '21.15'
SELECT MIN("Lane") FROM "table_79703" WHERE "Nationality" = 'brazil' AND "Time" < '21.15'