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【判断题】
因液控单向阀关闭时密封性能好,故常用在保压回路和锁紧回路中。( ) 2.普通单向阀用作背压阀时,弹簧换成软弹簧。( ) 3.液控单向阀控制油口不通压力油时,其作用与单向阀相同。( )
A.
正确
B.
错误
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【单选题】— Hurry up!It's already 8:20. — ________ ! It takes only 20 minutes to get to the station and the train doesn't leave until 9:20. [     ]
A.
No hurry
B.
No way
C.
No problem
D.
No chance
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【单选题】It takes her about 20 minutes _______to school.
A.
get
B.
gets
C.
getting
D.
to get
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【单选题】It only __________ him 20 minutes __________ to his office every day.
A.
takes; to  drive
B.
took; drive
C.
takes; drive D  takes took
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【判断题】已选择执行《企业会计准则》的小企业，不得在执行《企业会计准则》的同时，选择执行《小企业会计准则》的相关规定。( )
A.
正确
B.
错误
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【单选题】关于母儿间的血液交换，以下哪项错误
A.
母体血液以每分钟500ml的流速，经子宫螺旋动脉及其终末分支流入绒毛间隙
B.
母体与胎儿间的物质交换主要靠母体血液压力差，而非渗透、扩散及细胞选择力
C.
母儿间的物质交换非直接相通，血管合体膜是母儿进行物质交换的部位
D.
母体血液经底蜕膜螺旋动脉开口通向绒毛间隙，再经开口的螺旋静脉返回母体
E.
胎儿血液经脐动脉及其分支进入绒毛毛细血管，再经脐静脉返回胎儿体内
查看完整题目与答案
【单选题】Fifty years ago, most people lived in rural areas. But the world has changed. In the near future, more than half of all people will live in cities for the first time in history. City life is not alway...
A.
urbanization and its effects
B.
a huge effect of human
C.
economic development
D.
the environment
查看完整题目与答案
【单选题】Tom______half an hour doing his homework and listening to pop music ______him 20 minutes.
A.
costs; spends
B.
spends; take
C.
takes; costs
D.
spends; takes
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【单选题】It takes Mr Wang 20 minutes lunch every day.
A.
、 cook     
B.
、 to cook     
C.
、 cooking     
D.
、 cooks
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【单选题】It _______ me 20 minutes _______ to the park.
A.
spends ; to walk
B.
spends ; walking
C.
takes ; to walk
D.
takes ; walking
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【单选题】Tom takes 20 minutes to cook an egg and 5 minutes to make a sandwich. Jerry takes 15 minutes to cook an egg and 3 minutes to make a sandwich. Tom has a comparative advantage in ________ and Jerry has ...
A.
cooking eggs; making sandwiches
B.
making sandwiches; cooking eggs
C.
neither of these activities; both activities
D.
both activities; neither of these activities
查看完整题目与答案
相关题目：
【单选题】— Hurry up!It's already 8:20. — ________ ! It takes only 20 minutes to get to the station and the train doesn't leave until 9:20. [     ]
A.
No hurry
B.
No way
C.
No problem
D.
No chance
查看完整题目与答案
【单选题】It takes her about 20 minutes _______to school.
A.
get
B.
gets
C.
getting
D.
to get
查看完整题目与答案
【单选题】It only __________ him 20 minutes __________ to his office every day.
A.
takes; to  drive
B.
took; drive
C.
takes; drive D  takes took
查看完整题目与答案
【判断题】已选择执行《企业会计准则》的小企业，不得在执行《企业会计准则》的同时，选择执行《小企业会计准则》的相关规定。( )
A.
正确
B.
错误
查看完整题目与答案
【单选题】关于母儿间的血液交换，以下哪项错误
A.
母体血液以每分钟500ml的流速，经子宫螺旋动脉及其终末分支流入绒毛间隙
B.
母体与胎儿间的物质交换主要靠母体血液压力差，而非渗透、扩散及细胞选择力
C.
母儿间的物质交换非直接相通，血管合体膜是母儿进行物质交换的部位
D.
母体血液经底蜕膜螺旋动脉开口通向绒毛间隙，再经开口的螺旋静脉返回母体
E.
胎儿血液经脐动脉及其分支进入绒毛毛细血管，再经脐静脉返回胎儿体内
查看完整题目与答案
【单选题】Fifty years ago, most people lived in rural areas. But the world has changed. In the near future, more than half of all people will live in cities for the first time in history. City life is not alway...
A.
urbanization and its effects
B.
a huge effect of human
C.
economic development
D.
the environment
查看完整题目与答案
【单选题】Tom______half an hour doing his homework and listening to pop music ______him 20 minutes.
A.
costs; spends
B.
spends; take
C.
takes; costs
D.
spends; takes
查看完整题目与答案
【单选题】It takes Mr Wang 20 minutes lunch every day.
A.
、 cook     
B.
、 to cook     
C.
、 cooking     
D.
、 cooks
查看完整题目与答案
【单选题】It _______ me 20 minutes _______ to the park.
A.
spends ; to walk
B.
spends ; walking
C.
takes ; to walk
D.
takes ; walking
查看完整题目与答案
【单选题】Tom takes 20 minutes to cook an egg and 5 minutes to make a sandwich. Jerry takes 15 minutes to cook an egg and 3 minutes to make a sandwich. Tom has a comparative advantage in ________ and Jerry has ...
A.
cooking eggs; making sandwiches
B.
making sandwiches; cooking eggs
C.
neither of these activities; both activities
D.
both activities; neither of these activities
查看完整题目与答案