Name The Year: Soviet troops invade Yugoslavia.?

Questions

John Presper Eckert, co-inventor of first electronic computer (ENIAC), born.?

Hugh Hefner, publisher of Playboy, made bunnies famous, born.?

Mae West makes her New York City debut in a daring new play, "Diamond Lil".?

American and Filipino forces overwhelmed by Japanese at Bataan.?

U.S. Atomic Energy Commission confirmed.?