The Great Depression was a global economic crisis that may have been triggered by political decisions including war reparations post-World War I, protectionism such as the imposition of congressional tariffs on European goods or by speculation that caused the Stock Market Collapse of 1929
yes, he is right the answer is,
Galileo's most important scientific contributions were in the field of physics. ... Using the telescope, Galileo discovered the mountains on the moon, the spots on the sun, and four moons of Jupiter. His discoveries provided the evidence to support the theory that the earth and other planets revolved around the sun.
McClellan discovered General Robert E. Lee's battle plan.
Obviously, infiltration and access to battle plans allow for the opponent to figure out what their opponent's plans are, thus giving McClellan the victory at Antietam.
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