Answer:
Guam, Puerto Rico, and the Philippines
Unrestricted submarine warfare was first introduced in World War I in early 1915, when Germany declared the area around the British Isles a war zone, in which all merchant ships, including those from neutral countries, would be attacked by the German navy.
Lewis and Clark was sent to explore the Louisiana territory.
Hitler introduced many policies and measures to ensure the Nazis remained in control, once he declared himself Führer. These measures dealt with political opponents, as well as ordinary people, who suddenly found their private, social and working lives controlled by the Nazis.