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【简答题】
Read the Methodology section of this article.There are three paragraphs in 3.1 (M1, M2 and M3) and 5 paragraphs in 3.2 (M4, M5, M6, M7 and M8).What did the authors do to make standard gravity model suitable for this research?
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皮皮学刷刷变学霸
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【多选题】Why does the author say what they see is an increasingly appalling landscape? (Para. 5)
A.
There's smoke on the horizon, the blaze of battle fading.
B.
We pass by deserted villages, solitary, burned-out houses.
C.
We pass battlefields dense with the garbage of abandoned war equipment, bombed-out railway stations, overturned cars.
D.
It smells of gunpowder, and of burning, decomposing meat after a massacre. Everywhere are the corpses of horses.