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【简答题】
制冷机房中有两台相同的冷水机组,的声功率级为 82dB 。两台相同的循环水泵,的声功率级为 77dB 。一台补水泵,其声功率级为 80dB 。 不同声功率级叠加的附加值表 两个声功率及差值 / dB 4 5 6 7 8 9 10 15 附加值 / dB 1.5 1.2 1.0 0.8 0.6 0.5 0.4 0.1 求:这些设备设置在同一房间时,制冷机房最大的声功率级。
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【简答题】The Conference was a (succeed). We were all satisfied.
【单选题】Don't turn off the computer before closing all programs, you should have problems.
A.
or
B.
and
C.
but
D.
so
【单选题】One reason for water shortage is that ______.
A.
people in Europe don't turn off their taps
B.
people drill too many wells and pollute them
C.
the population has been continuously rising
D.
there is not much underground water
【单选题】Don't turn the stove off the meat ______.
A.
is cooked
B.
has been cooked
C.
is being cooked
D.
is cooking
【单选题】What is the best title for the text?
A.
Don't Turn Off Your Biological Clock.
B.
Day Working is Better Than Night Working.
C.
Night Workers: Be Careful.
D.
What is Bad of Night Working.
【单选题】Don't turn off the computer before closing all programs,_____ you could have problems.
A.
or
B.
and
C.
but
D.
so
【单选题】关于前期物业服务合同的说法，错误的是（ ）。
A.
前期物业服务合同具有过渡性
B.
前期物业服务合同属于要式合同
C.
前期物业服务合同以书面方式签订
D.
前期物业服务合同没有合同期限限制
【单选题】关于前期物业服务合同特点的说法，错误的是( )。
A.
前期物业服务合同由建设单位和物业服务企业签订
B.
前期物业服务合同属于书面合同
C.
前期物业服务合同的有效期须为3至5年
D.
前期物业服务合同属于附终止条件的合同
【单选题】Don't turn off the light, I a report now.
A.
have been reading
B.
read
C.
am reading
D.
have read
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