产生阻塞的原因不包括(15)。

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Password　is　a　secret　series　of(69)that　enables　a　user　to　access　a　file,　computer,　or　program.　On　multi-user　systems,　each　user　must　enter　his　or　her　password　before　the　computer　will　respond　to(70).　The　password　helps　ensure　that(71)users　do　not　access　the　computer.　In　addition,　data　files　and　programs　may　require　a　password.

A　multimedia　system　allows　end　users　to　share,　transfer　and　process　a　variety　of　forms　of　in-　formation　in　a(75)manller.

SQL　Server　is　a　RDBMS(　Relational　Database　Management　System)made　by　Microsoft.　This　means　that　the　data　is　stored　in　two　dimensional(74)