Professor James used student volunteers as ______ for his experiment.
A. models
B. cases
C. agents
D. subjects
查看答案
下列为膜剂成膜材料的是
A. 聚乙烯醇
B. 聚乙二醇
C. 交联聚维酮
D. 微晶纤维素
E. Poloxamer
What is the purpose of the conversation
A. To help the woman make a purchase.
B. To request the woman's identification.
C. To show the woman for a course at City College.
D. To register the woman how to make out a check.
Among people who suffer from colour blindness, ______ .
A. some may see everything in shades of green
B. few can tell the difference between blue and green
C. few may think that red, orange and yellow are all shades of green
D. very few may think that everything in the world is in green
What was the critic's to the novel.'
A. comment
B. impression
Comprehension
D. reaction
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