1) When was Archduke Ferdinand assassinated?
a) 28 June 1914
b) 4 August 1914
c) 6 June 1915
d) 7 July 1916
2) Which gas was used for the first time in World War I?
a) Chlorine
b) Nitrogen
c) Hydrogen
d) Helium
3) Which passenger ship of USA was sunk by Germany?
a) Titanic
b) Lusitania
c) Queen Mary
d) Repulse