CREATE TABLE table_47769 ("Name" TEXT, "Location" TEXT, "Elevation + Height" TEXT, "Delivery" TEXT, "Purpose" TEXT, "Yield" TEXT)

What is the yield in NTS Area U2R when the purpose is weapons development?
SELECT "Yield" FROM table_47769 WHERE "Purpose" = 'weapons development' AND "Location" = 'nts area u2r'
SELECT "Yield" FROM "table_47769" WHERE "Location" = 'nts area u2r' AND "Purpose" = 'weapons development'