假设某微处理器的主振频率为20MHz，两个时钟周期组成一个机器周期，平均4个机器周期可以完成一条指令，则其时钟周期为(12)ns　，平均运算速度为(13)MIPS。如果主振频率只有10MHz，则时钟周期为(14)ns，平均运算速度为(15)MIPS。若主振频率保持不变，而执行一条指令平均只需要两个机器周期，则平均运算速度可提高到(16)MIPS。

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When　you　think　of　the　Internet,　you　probably　think　of　".com."　Just　what　do　those　three　letters　at　the　end　of　a　World　Wide　Web　address　mean?　Every　computer　that　hosts　data　on　the　Internet　has　a(71)numerical　address.　For　example,　the　numerical　address　for　the　White　House　is　198.137.240.100.　But　since(72)people　want　to　remember　long　strings　of　numbers,　the(73)was　developed.　It　is　a　critical　part　of　the　Internet's　technical　infrastructure,　correlates　a　numerical　address　to　a　word.　To(74)the　White　House　website,　you　could　type　its　numerical　address　into　the　address　box　of　your　web　browser.　But　most　people　prefer　to　use　"www.　whitehouse.　gov."　In　this　case,　the　domain　name　is(75).

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The　most　accurate　and　most　boring　way　to(66)Java　is　that　it　is　a　new　computer　programming　language　developed　by　Sun　Microsystems　that　creates(67)independent　programs　that　can　be　distributed　and　run　remotely.　To　run　Java　programs,　a　computer　must　have　a　Java　interpreter.　Currently(68)Java　programs　are　small　"applets"　that　are(68)as　part　of　web　pages.

When　you　use　a　Java(69)browser　to　view　a　Web　page　that　includes　a　Java　applet,　the　browser　loads　the　applet　onto　your　computer　through　your　modem　or　network.　Then　the　Java　interpreter　runs　the　applet,　which　could　include　animation　or　sound,　on　your　computer　rather　than　transmitting　the　code　bit　by　bit　over　Internet.　A　few　thousand　bytes　of　Java　code　can　turn　into　a　powerful　program　on　your　computer.

So　an　applet　could　include(70)with　Java　interpreter.

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