CREATE TABLE table_26368 ("Week #" TEXT, "Theme" TEXT, "Song Choice" TEXT, "Original Artist" TEXT, "Order #" FLOAT, "Result" TEXT)

In what week was the original singer Whitney Houston.
SELECT "Week #" FROM table_26368 WHERE "Original Artist" = 'Whitney Houston'
SELECT "Week #" FROM "table_26368" WHERE "Original Artist" = 'Whitney Houston'