CREATE TABLE table_50240 ("State" TEXT, "Type" TEXT, "Name" TEXT, "Title" TEXT, "Royal house" TEXT)

What was the name listed for the royal house of jiang and a title of duke?
SELECT "Name" FROM table_50240 WHERE "Title" = 'duke' AND "Royal house" = 'jiang'
SELECT "Name" FROM "table_50240" WHERE "Royal house" = 'jiang' AND "Title" = 'duke'