Misc: Which dwarf is the leader of the dwarf's in "snow white"?

Questions

In 1917 USA declares ---------- on the Prussian-Hungarian forces, joining World War One on the side of the Allies. ?

In 1941 Japanese bomb ---------- Harbour. The USA join Allies in fighting the Axis forces soon after. ?

In 1971 (USA) Rube---------- , inventor and cartoonist, dies. ?

In 1934 Weekly airmail route starts between ---------- and the United Kingdom. ?

In 1941 The Allies, along with Free France declare war on---------- . ?