L型往复式压缩机，相邻两列的气缸中心线夹角为（）。 ["45°","60°","90°","120°"]
Which syntax turns an existing constraint on? （） [" ALTER TABLE table_name ENABLE constraint_name;"," ALTER TABLE table_name STATUS = ENABLE CONSTRAINT constraint _ name;"," ALTER TABLE table_name ENABLE CONSTRAINT constraint _ name;"," ALTER TABLE table_name TURN ON CONSTRAINT constraint _ name"]
黄某，因肾癌需行手术，其手术体位是（） ["折刀位","抬高腰桥侧卧位","平卧位","侧卧位","俯卧位"]
某施工单位承担一土石坝施工任务，该单位对坝基开挖做了施工组织设计，坝基基坑深为5.2m，采用药壶爆破法施工，土方量为9000m3，平均运距为10km，合同工期为8天。该施工单位有甲、乙、丙液压挖掘机各4台、2台、2台，A、B、C自卸汽车各12台、30台、18台，挖掘机的机械利用率为0.9，自卸汽车的机械利用率为0.95，其主要参数见表1、表2。
若每天一个台班，按上述最经济组合，安排挖掘机和自卸汽车的型号数量不变，应安排多少台、何种型号的挖掘机和自卸汽车，可以完成施工任务？
A customer is running an application with large block files that contain images and video files. They have a requirement for a low cost storage solution. The consultant recommended considering the NAS solution. Which of the following benefits will the NAS solution provide？（） ["Utilizes existing infrastructure","Provides direct host attached solution","NAS storage will use the reliable iSCSI protocol","Long distances after upgrading all host connections to fibre"]
乔木修剪
