下列单细胞生物中，始终不存在核仁和细胞壁结构的是（） ["支原体","蓝藻","乳酸菌","变形虫"]
分布式电源接入配电网自动化系统有哪些配置原则？
在“资源管理器”中用鼠标选定多个不连续的文件应先按住（）。 ["Shift+Alt键","Ctrl+Shift键","Shift键","Ctrl键"]
各单位建立监管员定期岗位轮换的制度，监管人员一般要求异地（）个月、本地一个月必须轮换。 ["一","二","三","四"]
Which factor determines the ring dam size for a fuel oil, tubular bowl type, centrifugal purifier?（） ["The viscosity off the fuel","The quantity of water to be removed from the fuel","The specific gravity of the fuel","The quantity of dirt to be removed from the fuel"]
简述对流烘燥法。
