两组计数资料的X2检验要求()
A.N>40.T≥5
B.N≥40,1≤T≤5
C.N随便,T≥1
D.NI>40,T随便
E.N随便,1≤T≤5
参考答案:B
试述激光的生物学效应及治疗作用。
The book provides tips for Westerners who work in Japanese firms: get together outside the office, find a mentor for support and refrain for practicing Japanese with colleagues on the job.
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