在一个关系R中，若存在X→（Y，Z），则存在X→Y，X→Z，称此为函数依赖的（）规则。
A. 传递性
B. 分解性
C. 合并性
D. 增广性
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ZPW-2000A/K轨道电路在轨道电路最不利条件下，使用标准分路电阻在轨道区段的任意点分路时，接收器接收电压（轨出1）原则上不大于（）mV，轨道电路可靠不工作。
A. 140
B. 153
C. 120
2015年在内蒙古招生的区内外普通高等学校共计1557所，计划招生160642人；其中，区外69023人、区内91619人；本科85130人、高职（专科）75512人。根据统计，今年，内蒙古约有（）%的考生可以上大学。
A. 67
B. 87
C. 75
D. 79
道岔开通手信号显示方法，旗信号为（）。
A. 展开的黄色旗高举头上左右摇动
B. 拢起的黄色旗高举头上左右摇动
C. 展开的黄色旗
D. 黄色旗下压数次
Mary has a view called EMP_DEPT_LOC_VU that was created based on the EMPLOYEES,DEPARTMENTS, and LOCATIONS tables. She granted SELECT privilege to Scott on this view. Which option enables Scott to eliminate the need to qualify the view with the name MARY .EMP_DEP_LOC_VU each time the view is referenced? （）
A. Scott can create a synonym for the EMP_DEPT_LOC_VU bus using the command: CREATE PRIVATE SYNONYM EDL_VU FOR mary. EMP DEPT_LOC_VU; then he can prefix the columns with this synonymn.
B. Scott can create a synonym for the EMP_DEPT_LOC_VU by using the command: CREATE SYNONYM EDL_VU FOR mary. EMP DEPT_LOC_VU; then he can prefix the columns with this synonym.
C. Scott can create a synonym for the EMP_DEPT_LOC_VU by using the command: CREATE LOCAL SYNONYM EDL_VU FOR mary. EMP DEPT_LOC_VU; then he can prefix the columns with this synonym.
D. Scott cannot create a synonym because synonyms can be created only for tables.
E. Scott cannot create any synonym for Mary's view. Mary should create a private synonym for the view and grant SELECT privilege on that synonym to Scott.
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