【单选题】碳素钢按碳的质量分数可分为低碳、中碳、高碳钢,中碳钢的质量分数一般是( )
【简答题】影响超声波测距的准确性有哪些因素?如何提高超声波测距仪的准确性?
【单选题】This is a _____ book that you may _____ in daily English study. [ ]
【多选题】病历摘要:患者女性,26岁,近半年来工作较为紧张劳累,休息欠佳,出现大便次数增多,每天约3~4次,质烂或稀,与情绪变化有关,便前伴有腹痛,便后腹痛缓解,但反复发作,曾检查肠镜未见明显异常,服用思密达、得舒特等药物可暂时缓解症状,但病情反复。现在仍然每次情绪紧张或激动时即欲大便,日3~4次,大便偶带有未消化食物,偶有黏液,无脓血,伴有胁肋、脘腹胀闷不舒,饮食减少,神疲,面色萎黄,体重稍有减轻。舌淡,...
【单选题】It's my daily duty to have the English newspapers ________ to the senior students. [ ]