CREATE TABLE table_74471 ("Townland" TEXT, "Area (  acres  ) " FLOAT, "Barony" TEXT, "Civil parish" TEXT, "Poor law union" TEXT)

What is the maximum area (in acres) of the Knockacullen townland?
SELECT MAX("Area( acres )") FROM table_74471 WHERE "Townland" = 'Knockacullen'
SELECT MAX("Area( acres )") FROM "table_74471" WHERE "Townland" = 'Knockacullen'