Which 1947 labor act made the closed-shop agreement illegal?

The 1946 Linggadjati Agreement gave grudging Dutch recognition to the authority of which island nation's republic? After pilot Kenneth Arnold's 1947 sighting, which two-word term for an alien craft entered the language? Which 1947 film starred Cary Grant and Shirley Temple? King Michael abdicated in 1947 as monarch of which Eastern European nation? Which artist painted "Christina's World" (1948)? Who directed and starred in the 1948 film "Hamlet"? Former vice president Henry Wallace ran for president in 1948 on which party's ticket? Which 1948 film includes the line usually misquoted as "We don't need no stinkin' badges"?