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【简答题】
对质点组有以下几种说法： (1)质点组总动量的改变与内力无关； (2)质点组总动能的改变与内力无关； (3)质点组机械能的改变与保守内力无关。 下列对上述说法判断正确的是( )。 (A) 只有(1)是正确的 (B) (1)、(2)是正确的 (C) (1)、(3)是正确的 (D) (2)、(3)是正确的
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皮皮学刷刷变学霸
举一反三
【单选题】Why did Wuhan Mental Health Center recruit more counselors?
A.
Because the center had received too many calls per day than before.
B.
Because 200 additional processionals had arrived at the center.
C.
Because some counselors complained that they couldn ’ t work.
D.
Because people were busy in fighting against COVID-19.
【单选题】This is an important concept to_______.
A.
get over
B.
get across
C.
get away
D.
get off
【单选题】Which of the following is NOT mentioned as a problem the counselors can help with?
A.
Strained relationship with boyfriend or girlfiend.
B.
Financial difficulties.
C.
Excessive tress of work.
D.
Death of a close.
【单选题】影响施工工程项目的因素主要包括五大方面，即工程中的4M1E。主要指（ ）。
A.
人材料机械方法和环境
B.
人（MAn）、材料(MAteriAl)、工具（MeAns）、方法(MethoD)和环境(Environment)
C.
人（MAn）、工具（MeAns）、机械(MA
D.
hine)、方法(MethoD)和环境(Environment)
E.
工具（MeAns）、材料(MAteriAl)、机械(MAChine)、方法(Metho
F.
)和环境(Environment)
【单选题】The counselors ______ the dormitory during the fire drill.
A.
scanned
B.
scrutinized
C.
explored
D.
swept
【单选题】Which of the following is NOT mentioned as a problem the counselors can help with?
A.
Strained relationship with boyfriend or girlfriend.
B.
Financial difficulties.
C.
Excessive stress of work.
D.
Death of a close.
【简答题】为跳汰机主要操作台的宽度不小于_____mm,另一侧操作台宽度应在____mm左右,以保证风、水闸的操作维修和管理布置。
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