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【多选题】
对于三相对称交流电路,不论星形或三角形接法,下列结论正确的有( )。A.
P= cosφ
B.
S=
C.
Q= sinφ
D.
S=
E.
S=3UI
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【单选题】On Monday， you dropped the DEPT table from your schema and then you re-created the DEPT table in your schema. On Wednesday， you have a requirement to restore the DEPT table from the recycle bin. Whic...
A.
You can restore the DEPT table by using the Oracle Flashback Drop feature， provided you use the RENAME TO clause.
B.
You can restore the DEPT table by using the Oracle Flashback Drop feature and a system-generated name will be assigned to the restored table.
C.
You cannot restore the DEPT table by using the Oracle Flashback Drop feature because a table with the name DEPT already exists in your schema.
D.
You cannot restore the DEPT table by using the Oracle Flashback Drop feature because the contents of the recycle bin are purged every 12 hours by default.
【单选题】Evaluate the following SQL statements in the given order: DROP TABLE dept? CREATE TABLE dept (deptno NUMBER(3) PRIMARY KEY, deptname VARCHAR2(10))? DROP TABLE dept? FLASHBACK TABLE dept TO BEFORE DROP...
A.
It recovers only the first DEPT table.
B.
It recovers only the second DEPT table.
C.
It does not recover any of the tables because FLASHBACK is not possible in this case.
D.
It recovers both the tables but the names would be changed to the ones assigned in the RECYCLEBIN.
【单选题】请选出不正确的一项（）
A.
口语交际过程是听与说的互动过程。
B.
口语交际过程，听的人不是被动的听众。
C.
说的人也不能只管自己说。
D.
听与说双方都是主动的，双方的角色是不能随时互换的。
【多选题】STK手机银行的特点有哪些?
A.
STK卡具有很高的存储量，能够运行应用软件
B.
STK手机银行可以办理多种业务手如金融理财、股票查询与交易、外汇买卖等
C.
每张STK卡只能使用一家银行的手机银行服务，难以实现跨行转账
D.
STK高成本和手续繁琐导致难以普及
【简答题】STK
【简答题】A．(dept_name，dept_phone，dept_mgrname) B．(emp_phone，dept_name) C．(emp_id，emp_phone，dept_name，dept_phone，dept_mgrname) D．(dept_phone，dept_mgrname)
【简答题】_______ A．Dept=DS B．Dept=DS WITH CHECK OPTl0N C．Dept='DS' D．Dept='DS' WITH CHECK OPTIoN A． B． C． D．
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