CREATE TABLE table_25754 ("No. in series" FLOAT, "No. in season" FLOAT, "Title" TEXT, "Directed by" TEXT, "Written by" TEXT, "Original air date" TEXT, "Production code" TEXT, "U.S. viewers  ( millions ) " TEXT)

What number episode in the series was written by David Zuckerman?
SELECT "No. in series" FROM table_25754 WHERE "Written by" = 'David Zuckerman'
SELECT "No. in series" FROM "table_25754" WHERE "Written by" = 'David Zuckerman'