UnScramble this Word: u e r n p m s a?

Questions

The first international cricket match ever, was held between Canada & _____?

The first modern Olympiad was held where?

The first nuclear chain reaction in 1942 by Enrico Fermi & Arthur Compton was achieved in what U S city?

The first nude Playboy centerfold was?

The first U S marines wore high leather collars to protect their necks from sabres, hence the term __________?