Why was portugal a good place for sea exploration

Immigrants arriving in the united states during the late 1800s experienced many difficulties. which of the following was a problem which large numbers of immigrants faced?

What were the nuremberg laws? who did they target and how? list 3 ways people were targeted by the nazis.

Why are the majority of the world's economies mixed? what may happen to the "pure" types of economies (traditional, socialist/command, market capitalist) when they incorporate elements from other economic models?