CREATE TABLE table_4814 ("Rank" FLOAT, "Heat : Lane" TEXT, "Name" TEXT, "Nationality" TEXT, "Time" TEXT)

How many ranks have a ationality of canada, and a Time of dns?
SELECT COUNT("Rank") FROM table_4814 WHERE "Nationality" = 'canada' AND "Time" = 'dns'
SELECT COUNT("Rank") FROM "table_4814" WHERE "Nationality" = 'canada' AND "Time" = 'dns'