27岁初孕妇。妊娠35周，头痛6天，经检查血压160/110mmHg，治疗3天无显效。今晨5时突然出现剧烈腹痛。检查子宫板状硬，胎位扪不清，胎心消失。最可能的诊断是（） ["妊娠合并急性阑尾炎","胎盘早剥","前置胎盘","先兆子宫破裂","先兆早产"]
KY-250A型牙轮钻机行走速度为（）km/h。 ["0.63","0.73","0.75","0.76"]
KY-250A型牙轮钻机均衡张紧压力为（）MPa。 ["2.5","3.0","3.5","4.0"]
KY系列牙轮钻机移车通过路面，在5X5米范围内不平度不得超过（）mm。 ["200","250","300","350"]
血清中的C1作用对象是（）。 ["C2a C3a","C3a C5a","C3b C4b","C2 C4","C5a C3"]
钢筋工程施工组织一般可分为哪几个阶段？
