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【单选题】
设正实数x,y,z满足x 2 -3xy+4y 2 -z=0,则当 取得最大值时,x+2y-z的最大值为(　　)
A.
0
B.
C.
2
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举一反三
【单选题】'You've got already well, haven't you?' she asked. →She asked _____.    . [     ]
A.
if I have already got well, hadn't you
B.
whether I had got well
C.
have I already got well
D.
had I already got well
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【简答题】You've just finished you’re a-levels and you've got a place at university, but you'd really like a break from the academic world. Why not think about taking a year out? While most students go__61 from...
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【单选题】听力原文：W: What keeps you so busy? You've been sitting there for hours. You've got to walk around. Let's take a coffee break. M: Well, I wish I could, but I'm up to my neck in work. I've got to finish th...
A.
He will take a coffee break.
B.
He will keep on working.
C.
He will go for a walk.
D.
He will begin with the report.
查看完整题目与答案
【单选题】听力原文：W: What keeps you so busy? You've been sitting there for hours. You've got to walk around. Let's take a coffee break. M: Well, I wish I could, but I'm up to nay neck in work. I've got to finish t...
A.
He will take a coffee break.
B.
He will keep on working.
C.
He will go for a walk.
D.
He will begin with the report.
查看完整题目与答案
【单选题】Which of the following is not prefixes indicating measures and weights ?
A.
centi
B.
kilo
C.
mini
D.
multi
查看完整题目与答案
【单选题】下列关于M受体叙述哪项是错误的?
A.
属于胆碱能受体    
B.
与乙酰胆碱结合
C.
可以与毒蕈碱结合    
D.
存在于神经肌肉接头的终板膜上
E.
阿托品是M受体的阻断剂
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【单选题】Hence obstacles are created ____ countries use different formats for weights, measures, dates, telephone numbers, addresses, and other common information.
A.
if
B.
unless
C.
because
D.
even if
查看完整题目与答案
【单选题】"下列关于M受体叙述,哪项是错误的?
A.
属于胆硷能受体
B.
可以与乙酰胆硷结合
C.
可以与毒蕈硷结合
D.
存在于神经肌肉接头的终板模上
E.
阿托品是M受体的阻断剂
查看完整题目与答案
【单选题】Units under the International System and those systems decided by the ______ are statutory units of weights and measures . A. government B.manufacturer C. importer D. exporter
A.
government
B.
manufacturer
C.
importer
D.
exporter
查看完整题目与答案
【单选题】At present, which of the following is NOT the system of weights and measures commonly used in international trade?
A.
SI.
B.
The French system.
C.
The British system.
D.
The metric system.
查看完整题目与答案
相关题目：
【单选题】'You've got already well, haven't you?' she asked. →She asked _____.    . [     ]
A.
if I have already got well, hadn't you
B.
whether I had got well
C.
have I already got well
D.
had I already got well
查看完整题目与答案
【简答题】You've just finished you’re a-levels and you've got a place at university, but you'd really like a break from the academic world. Why not think about taking a year out? While most students go__61 from...
查看完整题目与答案
【单选题】听力原文：W: What keeps you so busy? You've been sitting there for hours. You've got to walk around. Let's take a coffee break. M: Well, I wish I could, but I'm up to my neck in work. I've got to finish th...
A.
He will take a coffee break.
B.
He will keep on working.
C.
He will go for a walk.
D.
He will begin with the report.
查看完整题目与答案
【单选题】听力原文：W: What keeps you so busy? You've been sitting there for hours. You've got to walk around. Let's take a coffee break. M: Well, I wish I could, but I'm up to nay neck in work. I've got to finish t...
A.
He will take a coffee break.
B.
He will keep on working.
C.
He will go for a walk.
D.
He will begin with the report.
查看完整题目与答案
【单选题】Which of the following is not prefixes indicating measures and weights ?
A.
centi
B.
kilo
C.
mini
D.
multi
查看完整题目与答案
【单选题】下列关于M受体叙述哪项是错误的?
A.
属于胆碱能受体    
B.
与乙酰胆碱结合
C.
可以与毒蕈碱结合    
D.
存在于神经肌肉接头的终板膜上
E.
阿托品是M受体的阻断剂
查看完整题目与答案
【单选题】Hence obstacles are created ____ countries use different formats for weights, measures, dates, telephone numbers, addresses, and other common information.
A.
if
B.
unless
C.
because
D.
even if
查看完整题目与答案
【单选题】"下列关于M受体叙述,哪项是错误的?
A.
属于胆硷能受体
B.
可以与乙酰胆硷结合
C.
可以与毒蕈硷结合
D.
存在于神经肌肉接头的终板模上
E.
阿托品是M受体的阻断剂
查看完整题目与答案
【单选题】Units under the International System and those systems decided by the ______ are statutory units of weights and measures . A. government B.manufacturer C. importer D. exporter
A.
government
B.
manufacturer
C.
importer
D.
exporter
查看完整题目与答案
【单选题】At present, which of the following is NOT the system of weights and measures commonly used in international trade?
A.
SI.
B.
The French system.
C.
The British system.
D.
The metric system.
查看完整题目与答案
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