单项选择题
A.40~100mm B.60~120mm C.80~160mm D.100~180mm
A.70~100mm B.80~120mm C.120~160mm D.140~180mm
A.1020mm B.1040mm C.1050mm D.1060mm
A.22.5t B.22.5×(1±3%)t C.23×(1±3%)t D.(23+2)t
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