CREATE TABLE table_75744 ("Name" CLOB, "Builder" CLOB, "Laid down" CLOB, "Launched" CLOB, "Completed" FLOAT)

When did chatham complete the Hmsmedusa?
SELECT "Completed" FROM table_75744 WHERE "Builder" = 'chatham' AND "Name" = 'hmsmedusa'
SELECT "Completed" FROM "table_75744" WHERE "Builder" = 'chatham' AND "Name" = 'hmsmedusa'