CREATE TABLE table_57167 ("Round" FLOAT, "Grand Prix" TEXT, "Date" TEXT, "Location" TEXT, "Pole Position" TEXT, "Fastest Lap" TEXT, "Winning Driver" TEXT, "Winning Constructor" TEXT, "Report" TEXT)

What is the highest round on 5 april?
SELECT MAX("Round") FROM table_57167 WHERE "Date" = '5 april'
SELECT MAX("Round") FROM "table_57167" WHERE "Date" = '5 april'