The last frontiers to be mapped are the Polar regions. They were discovered something about between 1925 and 1935.
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The answer is A.
Rockefeller worked with oil, Vanderbilt did the railroads, Carnegie was leader of the American steel industry, and Astor did fur trade and invested in real estate.
Answer:
I believe its my natural right to request trial by combat.
It would encourage Europeans to launch campaigns and
expeditions to expand travel and trade.
Seeing goods that are new to them would spur them to find routes to
reach these lands and establish trade relations with them as well learn new
things that would benefit their societies.
D The government was slow to respond and most of the victims were affluent whites.
