语文教育学的教学目的是什么？
衡量计算机及网络安全的主要指标是（） 保密性、及需性、完整性。 保密性、完整性、不可否认性。 完整性、保密性、可用性。 完整性、保密性、辨识性。
Examine the data in the EMPLOYEES and DEPARTMENTS tables: Also examine the SQL statements that create the EMPLOYEES and DEPARTMENTS tables: On the EMPLOYEES table, EMPLOYEE_ID is the primary key. MGR_ID is the ID of managers and refers to the EMPLOYEE_ID. DEPT_ID is foreign key to DEPARTMENT_ID column of the DEPARTMENTS table. On the DEPARTMENTS table, DEPARTMENT_ID is the primary key. Examine this DELETE statement: What happens when you execute the DELETE statement?（） Only the row with department ID 40 is deleted in the DEPARTMENTS table.。 The statement fails because there are child records in the EMPLOYEES table with department ID 40.。 The row with department ID 40 is deleted in the DEPARTMENTS table. Also the rows with employee IDs 110 and 106 are deleted from the EMPLOYEES table.。 The row with department ID 40 is deleted in the DEPARTMENTS table. Also the rows with employee IDs 106 and 110 and the employees working under employee 110 are deleted from the EMPLOYEES table.。 The row with department ID 40 is deleted in the DEPARTMENTS table. Also all the rows in the EMPLOYEES table are deleted.。 The statement fails because there are no columns specifies in the DELETE clause of the DELETE statement.。
机械密封由几部分组成？
就论证端午节是中国历史悠久的传统节日而言，下列哪方面的证据应当最有说服力（）。 古籍的记载。 屈原的作品。 政府的声明。 学者的解释。
若车辆仅在某种情况下在某段运营时间内上线工作，并且一日连续工作时间累计不超过一个工作班，则这种车辆称为（）。
