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问题 单项选择题

中药地黄加工炮制后变黑，原因是地黄含有哪类成分所致

A．环烯醚萜
B．二葸酮
C．黄烷醇
D．木脂素
E．皂苷

答案

参考答案：A

解析：地黄的有效成分梓醇为环烯醚萜苷，水解后的苷元不稳定，易变为深色。

单项选择题

增值税率为13%的纳税人和营业税率为3%的纳税人的无差别平衡点增值率为（）。

A．34.41%

B．43.46%

C．26.07%

D．20.64%
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单项选择题

The first and most important agents of socialization are the people who care for infants. In the earliest months, messages from nurturers constitute the child’’s basic understanding of the world around it. This is the infant’’s first introduction to the language that shapes perception and elicits emotion.Another powerful source of information and socialization is the friendship of peers. Peers are equals that one can deal with on the same level as oneself, whereas parents are superiors. The heavy emotional overlay of family relationships makes some kinds of learning difficult.Much formal socialization is placed in the hands of professionals. Teachers from kindergarten on are specifically designated agents of socialization. Ideally, a teacher is one who has both knowledge and the skills to present it. During the course of teaching their subjects, classroom instructors provide role models and attempt to convey the excitement of learning itself.In earlier times, parents, friends and teachers would comprise the list of primary childhood socializers. Children’’s books, comics and magazines might also have been mentioned as sources of information on norms and role models. Today one must add three powerful indirect or non-personal socialization agents: radio, movies and television. Many people learn about politics, form a vision of well-being, and develop attitudes towards others from what they see on the screen and hear through the speakers.

Which of the following statements is NOT true

A．Language shapes an infant’s perception.

B．Language elicits an infant’s emotions.

C．Language forms an infant’s cultural awareness.

D．Language forms an infant’s basic understanding.
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