Answer:
B: Bronze
Explanation:
Because this brought humans into the bronze/copper age. And bronze is a copper and tin alloy
Answer:
Impact of Dunkirk While the German blitzkrieg was undoubtedly successful (France would call for an armistice by mid-June 1940), the largely successful evacuation of the bulk of Britain's trained troops from near-annihilation proved to be a key moment in the Allied war effort.

Andrew Johnson's behavior in office hurt the cause of the Reconstruction era, since he abandoned many of the more-liberal policies that he had trumpeted earlier, leading to a federal abandonment of the oversight process in the South.
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