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【简答题】
已知向量 （1）求 ； （2）当 时，求 的值.
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皮皮学刷刷变学霸
举一反三
【判断题】Universal facial expressions do exist, but cultural norms often dictate how, when, and to whom facial expressions are displayed.
A.
正确
B.
错误
【单选题】OR 值准确估计RR值的条件不包括下列哪一个?
A.
所研究因素在人群中的暴露比例不能太低
B.
没有选择偏倚
C.
没有信息偏倚
D.
所研究疾病是罕见病
E.
以上都不是
【简答题】An experiment with people from Papua New Guinea (prove) _______ that some facial expressions are universal.
【单选题】Charles Darwins The Expression of the Emotions in Man and Animals proposed that facial expressions might
A.
act as a simple tool of cross-cultural communication.
B.
get people ready to the changes of circumstances.
C.
be difficult to understand in different cultures.
D.
equip people with the knowledge of other species.
【单选题】Which one does not belong to six universal facial expressions?
A.
sadness
B.
disappointment
C.
disgust
D.
surprise
【简答题】简述眼的组成和作用。
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