如何评价筛分设备的使用效果？怎样计算筛选效率？
坚持党的基本路线必须坚持四项基本原则，下列命题中不属于四项基本原则的是（） ["坚持中国共产党的领导","坚持社会主义道路","坚持人民民主专政","坚持改革开放"]
A table was just created on your Oracle database with six extents allocated to it. Which of the following factors most likely caused the table to have so many extents allocated?（） ["The value for MINEXTENTS setting ","The value for PCTINCREASE setting ","The value for MAXEXTENTS setting ","By default, Oracle allocates six extents to all database object"]
客户关系（）指在企业与客户关系建立初期，客户刚刚开始对企业产品或服务感兴趣，并开始收集有关信息。
逆止保护装置的作用是（）。 ["防止输送带跑偏","防止输送带松弛","防止逆转飞车","防止输送带撕裂"]
板翅式、浮头式、套房式换热器有哪些优缺点？
