问题
选择题
It is said that his missing paintings were ________the possession of Russians and they were valued
________$500, 000. [ ]
A. in; to
B. in; at
C. under; at
D. to; for
答案
答案：B
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It is said that his missing paintings were ________the possession of Russians and they were valued
________$500, 000. [ ]
A. in; to
B. in; at
C. under; at
D. to; for
答案：B
，导体棒ab的动能为EK，此过程中两根导体棒、导体棒与磁铁之间没有发生碰撞，求