Cho các chất : phenol, stiren, benzen, toluen, anilin, triolein, glixerol. Số chất tác dụng được với nước brom là

A. 6

B. 5

C. 4

D. 3

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions.

By adopting a few simple techniques, parents who read to their children can substantially increase their children’s language development. It’s surprising, but true. How parents talk to their children makes a big difference in the children’s language development. If a parent encourages the child to actively respond to what the parent is reading, the child’s language skills increase.

A study was done with 2 to 3 year-old children and their parents. Half of the thirty children participated in the experimental study; the other half acted as the control group. In the experimental group, the parents were given a two-hour training session in which they were taught to ask open-ended questions rather than yes/no questions. For example, the parent should ask, “what is the doggie doing?” rather than, “Is the doggie running away?” Experimental parents were also instructed in how to expand on their children’s answers, how to suggest alternative possibilities, and how to praise correct answers.

At the beginning of the study, the children did not differ on measures of language development, but at the end of one month the children in the experimental group tested 5.5 months ahead of the control group on a test of verbal expression and vocabulary. Nine months later, the children in the experimental group still showed an advance of 6 months over the children in the control group.

How many children were there in the study?

A. 2 or 3

B. 15

C. 30

D. 60

-phôi phát triển trog cơ thể mẹ nên an toàn và có điều kiện sống thích hợp

-phôi đc mẹ cung cập chất dinh dưỡng qua nhau. Sự phát triển của phôi ko phụ thuộc vào lượng noãn hoàng có trg trứng

-con non đc nuôi = sữa mẹ, ko lệ thuộc vào lượng thức ăn ngoài tự nhiên như trứng

Mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the following questions.

_____________ Nam Cao is a realistic writer, but he still used a lot of romance in his stories.

A. On my part

B. On the contrary

C. On the other hand 

D. On the whole

Rút gọn rồi qui đồng mẫu các phân số:

- 15 90 ;   120 600 ;   - 75 150

45 ⁰

ảnh ảo: ảnh trong gương

ảnh thật: cái bóng của chúng ta