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【单选题】
在关系代数中，对有公共属性的两个关系做自然连接之后，新关系的元组个数与原来两个关系的元组个数之和相比较，是< )。
A.
等于
B.
不确定
C.
大于
D.
小于
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【单选题】—There are always many volunteers in great events, _______? —Yes. Many hands make light work ! [     ]
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【单选题】–There are always many volunteers in great events, ________? --Yes. Many hands make light work.
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【单选题】It took many hands to ______ the cotton crop before the invention of machinery.
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【判断题】中国历史上有外戚势力和宦官势力来干涉朝政的势力，且最早的宦官出现在秦朝。
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【单选题】下列关于Lp(a)叙述错误的是
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【单选题】It took many hands to __ the cotton crop before the invention of machinery.
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B.
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roast
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【单选题】It took many hands to ______ the cotton crop before the invention of machinery.
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【判断题】中国历史上有外戚势力和宦官势力来干涉朝政的势力，且最早的宦官出现在秦朝。
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【单选题】下列关于Lp(a)叙述错误的是
A.
Lp(a)是动脉粥样硬化性疾病的独立危险因子
B.
Lp(a)水平在个体间相差较大
C.
Apo(a)与纤溶酶原具有高度同源性
D.
Apo(a)可从Lp(a)上脱落下来,剩下不含Apo(a)而仅含ApoB100的颗粒称LDL
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肝脏是Lp(a)合成的主要场所
查看完整题目与答案