CREATE TABLE table_37356 ("Call sign" TEXT, "Frequency MHz" FLOAT, "City of license" TEXT, "ERP W" FLOAT, "Class" TEXT, "FCC info" TEXT)

What is the Class for the ERP W of more than 2 and the call sign of w223au?
SELECT "Class" FROM table_37356 WHERE "ERP W" > '2' AND "Call sign" = 'w223au'
SELECT "Class" FROM "table_37356" WHERE "Call sign" = 'w223au' AND "ERP W" > '2'