______ has the most potential art buyers.
America
B. Hong Kong
C. Japan
D. India
在肌细胞兴奋-收缩耦联过程中起媒介作用的离子是
A. Na+
B. Cl-
C. K+
D. Ca2+
Max could be best described as ______.
A. lenient and permissive
B. eager to please his students
C. disgusting and loathsome
D. strict and demanding
气体扩散速率与下列哪个因素呈反比
A. 气体分压差
B. 气体扩散面积
C. 气体扩散距离
D. 气体溶解度
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