单项选择题
A.2 B.20 C.102 D.104
A.A1/A2=4 B.A1/A2=2 C.A1/A2=16 D.A1/A2=1/4
A.λ/2 B.λ/4 C.3λ/4 D.λ
A.2V0 B.1/2V0 C.V0 D.3/2V0
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