下列塑料流动性好的有()。 ["尼龙","聚乙烯","聚苯乙烯","聚碳酸脂","聚氯乙烯"]
CM40支美细细纱车速16000转/分,捻度24捻,折50支车速15850转/分、捻度27.85捻,折合系数为() ["A、0.784","B、0.682","C、0.696","D、0.762"]
《海上船舶防止油污证书》中填写的建造日期应为下列哪一个日期?() ["A、船舶图纸批准日期","B、船舶安放龙骨日期","C、船舶分段建造日期","D、船舶分段合拢日期"]
根据国家标准,常用的钢铆钉材料有()。 ["45钢","LF10","Q235","T3"]
细纱各品种折50支折合系数计算公式() ["A、(50S细纱锭速×某种纱捻度×某种纱支)/某种纱细纱锭速×50S纱捻度×50","B、(某种纱细纱锭速×某种纱捻度×某种纱支)/50S细纱锭速×50S纱捻度×50","C、(某种纱细纱锭速×50S纱捻度×某种纱支)/50S细纱锭速×某种纱捻度×50","D、以上都不对"]
加强磨内通风有哪些好处?