Có những chất sau :    NaHCO 3 ,  Ca OH 2 ,  CaCl 2 ,  CaCO 3 . Chất nào tác dụng được với dung dịch NaOH ? Viết các phương trình hoá học

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

          Telecommunicating is a form of computer communication between employees’ homes and offices. For employees whose jobs involve sitting at a terminal or word processor entering data or typing reports, the location of the computer is of no consequence. If the machine can communicate over telephone lines, when the work is completed, employees can dial the office computer from a distant site and transmit the material to their employers. A recent survey in USA Today estimates that there are approximately 8.7 million telecommuters. But although the numbers are rising annually, the trend does not appear to be as significant as predicted when Business Week published "The Portable Executive" as its cover story a few years ago. Why hasn't telecommuting become more popular?

          Clearly, change simply takes time. But in addition, there has been active resistance on the part of many managers. These executives claim that supervising the telecommuters in a large work force scattered across the country would be too difficult, or, at least, systems for managing them are not yet developed, thereby complicating the manager's responsibilities.

          It is also true that employees who are given the option of telecommuting are often reluctant to accept the opportunity. Most people feel that they need regular interaction with a group, and many are concerned that they will not have the same consideration for advancement if they are not more visible in the office setting. Some people feel that even when a space in their homes is set aside as a work area, they never really get away from the office.

The author mentions all of the following as concerns of telecommuting EXCEPT ___________

A. the different system of supervision

B. the opportunities for advancement 

C. the lack of interaction with a group

D. The work place is in the home

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 from .

           Martin Luther King, Jf., is well- known for his work in civil rights and for his many famous speeches, among which is his moving “ I have a dream” speech. But fewer people know much about King’s childhood. M.L., as he was called, was born in 1929 in Atlanta, Georgia, at the home of his maternal grandfather. M.L.’s grandfather purchased their home on Auburn Avenue in 1909, twenty years before M.L was born. His grandfather allowed the house to be used as a meeting place for a number of organizations dedicated to the education and social advancement of blacks. M.L. grew up in the atmosphere, with his home being used as a community gathering place, and was no doubt influenced by it.

          M.L.’s childhood was not especially eventfully. His father was a minister and his mother was a musician. He was the second of three children, and he attended all black schools in a black neighborhood. The neighborhood was not poor, however. Auburn Avenue was an area of banks, insurance companies, builders, jewelers, tailors, doctors, lawyers, and other businesses and services. Even in the face of Atlanta’s segregation, the district thrived. Dr. King never forgot the community spirit he had known as a child, nor did he forget the racial prejudice that was a huge barrier keeping black Atlantans from mingling with whites.

What is Martin Luthur King well- known for?

A. His publications.

B. His neighborhood.

C. His childhood.

D. His work in civil rights.

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 question below.

We find that bright children are rarely held back by mixed-ability teaching. On the contrary, both their knowledge and experience are enriched. We feel that there are many disadvantages in streaming pupils. It does not take into account the fact that children develop at different rates. It can have a bad effect on both the bright and the not-so-bright child. After all, it can be quite discouraging to be at the bottom of the top grade!

Besides, it is rather unreal to grade people just according to their intellectual ability. This is only one aspect of their total personality. We are concerned to develop the abilities of all our pupils to the full, not just their academic ability. We also value personal qualities and social skills, and we find that mixed-ability teaching contributes to all these aspects of learning.

In our classroom, we work in various ways. The pupils often work in groups; this gives them the opportunity to learn to co-operate, to share, and to develop leadership skills. They also learn how to cope with the personal problems as well as learning how to think, to make decisions, to analyze and evaluate, to communicate effectively. The pupils learn from each other as well as from the teachers.

Sometimes the pupils work in pairs; sometimes the work on individual tasks and assignments, they can do this at their own speed. They also have some formal class teaching when this is appropriate. We encourage our pupils to use the library, and we teach them the skills they need in order to do this effectively. An advanced pupil can do advanced works; it does not matter what age the child is. We expect our pupils to do their best, not their least, and we give them every encouragement to attain this goal

The author’s purpose of writing this passage is to _________

A. recommend pair work and group work classroom activities

B. offer advice on the proper use of the school library

C. argue for teaching bright and not-so-bright pupils in the same class

D. emphasize the importance of appropriate formal classroom teaching

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 from 26 to 34.

Although noise, commonly defined as unwanted sound, is a widely recognized form of pollution, it is very difficult to measure because the discomfort experienced by different individuals is highly subjective and, therefore, variable. Exposure to lower levels of noise may be slightly irritating, whereas exposure to higher levels may actually cause hearing loss. Particularly in congested urban areas, the noise produced as a by-product of our advancing technology causes physical and psychological harm, and detracts from the quality of life for those who are exposed to it.

Unlike the eyes, which can be covered by the eyelids against strong light, the ear has no lid, and is, therefore, always open and vulnerable; noise penetrates without protection. Noise causes effects that the hearer cannot control and to which the body never becomes accustomed. Loud noises instinctively signal danger to any organism with a hearing mechanism, including human beings. In response, heartbeat and respiration accelerate, blood vessels constrict, the skin pales, and muscles tense. In fact, there is a general increase in functioning brought about by the flow of adrenaline released in response to fear, and some of these responses persist even longer than the noise, occasionally as long as thirty minutes after the sound has ceased. Because noise is unavoidable in a complex, industrial society, we are constantly responding in the same way that we would respond to danger. Recently, researchers have concluded that noise and our response may be much more than an annoyance. It may be a serious threat to physical and psychological health and well-being, causing damage not only to the ear and brain but also to the heart and stomach. We have long known that hearing loss is America's number one nonfatal health problem, but now we are learning that some of us with heart disease and ulcers may be victims of noise as well. Fetuses exposed to noise tend to be overactive, they cry easily, and they are more sensitive

to gastrointestinal problems after birth. In addition, the psychic effect of noise is very important. Nervousness, irritability, tension, and anxiety increase affecting the quality of rest during sleep, and the efficiency of activities during waking hours, as well as the way that we interact with each other

It can be inferred from the passage that the eye ___.

A.  responds to fear

B. enjoys greater protection than the ear

C.  increases functions

D. is damaged by noise

Hỗn hợp X gồm Al, Fe₂O₃ có khối lượng 21,67 gam. Tiến hành phản ứng nhiệt nhôm hỗn hợp X trong điều kiện không có không khí (giả thiết chỉ xảy ra phản ứng Al khử Fe₂O₃ thành kim loại). Hòa tan hỗn hợp chất rắn sau phản ứng bằng dung dịch NaOH dư thu được 2,016 lít H₂ (đktc) và 12,4 gam chất rắn không tan. Hiệu suất của phản ứng nhiệt nhôm là:

A. 45%

B. 50%

C. 80%

D. 75%

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 from 35 to 44.

Charles Lindbergh was born in Detroit, Michigan, in 1902 but was raised on a farm in Minnesota, where his father was elected to the U.S. Congress in 1907. From then on, he spent his boyhood alternately in Washington, D.C, and Little Falls, Minnesota. Because Lindbergh exhibited exceptional mechanical talent, in 1921 he was admitted to the university of Wisconsin to study engineering. However the young man was seeking more challenging endeavors, and two years later he became a stunt pilot who performed feats at county fairs and public assemblies. This unusual and dangerous undertaking paid off handsomely in the sense that it allowed him to gain a diverse and well- rounded experience in aeronautics. He particularly delighted in what he called "wing-walking" and parachute jumping.

After a year of training as a military cadet, Lindbergh completed his program at the Brooks and Kelly airfields at the top of his class and earned the rank of captain. Roberton Aircraft Corporation of St. Louis, Missouri, offered him employment as a mail pilot to run the routes between St. Louis and Chicago, and Lindbergh retained his position with the company until 1927. During this period, he set out to win the Raymond B. Orteig prize of $ 25,000 to be awarded to the first pilot to fly nonstop from New York to Paris. This ambition would irreversibly change his life and accord him a prominent place in the history of aviation.

Embarking on the greatest adventure of his time, Lindbergh left Roosevelt Field at 7:52 A.M on May, 20, 1927, and landed at Bourget Field at 5:24 P.M the next day. Fearing that he would be unknown when he arrived, Lindbergh carried letters of introduction to dignitaries in Paris, but when his plane came to a stop, he was overwhelmed by tremendous welcoming crowds. He was decorated in France, Great Britain, and Belgium, and President Coolidge sent a specially designated cruiser, the Memphis, to bring him back. His accomplishments in aeronautics brought him more medals and awards than had ever been received by any other person in private life. 

The word “handsomely” is closest in meaning to

A. honorably                 

B. handily            

C. well                           

D. in time

A: Your speech this morning was just beyond my expectation.

B: __________.

A. It's OK

B. Not at all. It was just OK

C. It was my pleasure

D. Thanks. Without your help, I couldn't have done it.