D. mound builders
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Europeans were originally motivated to explore the seas to discover previously unknown lands, especially after the contact with America, where europeans found all kind of valuable goods. The portuguese were the first to pursue maritime exploration, soon to be followed by the spaniards.
Answer:
Narrator: The success of large speculators like Livermore and Durant lured smaller investors to Wall Street, but Charles Mitchell, president of National City Bank, virtually invented the idea of mass-marketing stocks and bonds to the general public. This was a totally new idea and a huge success.
Answer:
The USA became involved in Vietnam because it feared the spread of communism.
Explanation: