单项选择题
A.20minB.0.5hC.40minD.1h
A.(20±2)℃B.(25±2)℃C.(30±2)℃D.(250±2)℃
A.30cmB.40cmC.50cmD.60cm
A.预夹持距离变大,卷曲数变大B.预夹持距离变大,卷曲数变小C.预夹持距离是设定好的,与测试结果无关D.预夹持距离变小,卷曲数变大
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