题目内容

羟基蒽醌中,酸性最强的是

A. 1-羟基蒽醌
B. 2-羟基蒽醌
C. 1,2-二羟基蒽醌
D. 1,8-二羟基蒽醌
E. 3,6-二羟基蒽酉昆

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Americans usually eat three meals a day. Breakfast usually comes before eight o’clock in the morning. They usually have eggs, some meat, bread, fruit juice and coffee. Lunch, is between twelve and one o’clock. It is a light meal and working people most take lunch with them or get it near their workplace. Children in school take sandwiches, fruit, and cookies with them or eat in school. Supper, the main meal, is between six and eight in the evening. People cook it carefully. They may have meat or chicken, turkey or duck. They may all have potatoes or rice, vegetables or salad. The drink is coffee, tea or milk. Then comes the dessert. Americans have breakfast ______.

A. at eight o’clock
B. in the morning
C. before eight o’clock in the morning

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