Tam thức nào sau đây nhận giá trị âm với mọi ?

Với  thuộc tập hợp nào dưới đây thì nhị thức bậc nhất không âm

Tam thức  nhận giá trị âm khi và chỉ khi

 Bảng xét dấu nào sau đây là bảng xét dấu của tam thức ?

Bảng xét dấu nào sau đây là bảng xét dấu của tam thức ?

 Tam thức nào sau đây nhận giá trị âm với mọi ?

Bảng xét dấu nào sau đây là bảng xét dấu của tam thức ?

Tam thức nào sau đây nhận giá trị âm với mọi ?

 Với  thuộc tập hợp nào dưới đây thì không âm?

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct word or phrase that best fits each of the numbered blanks:   

There are several changes in the procedure for employees ___5___ wish to apply for vacant positions within the company. These changes make it much easier for in-house employees to fill vacancies that occur. First, __6__ most important difference is that employees will now be notified of all available positions before the positions are advertised for the general public. Accordingly, all in-house candidates will be interviewed before we see any out-side candidates, and we will offer the job to outside candidates only if no current employees are able to fill the position. Second, under the new procedure, in-house employees can be hired even if they don’t __7__ all job requirements. Under our old policy, in-house employees had to meet all job qualifications in order to obtain the vacant position. Now, however, employees who have proven themselves dedicated __8__ the company will be hired for a vacant position even if they are lacking some minor qualifications; training will be provided. A third change involves recommendations. Form now on, employees do not need to be recommended for an in-house position before they __9__. Instead, employees may apply as soon as they are aware of the vacancy. The remaining procedures and policies (those regarding increase in pay, interview procedure, and hiring approval) remain the same.

Question 9:

Dãy nào sau đây chỉ gồm các chất vừa tác dụng được với dung dịch HCl, vừa tác dụng được với dung dịch AgNO3 ?  

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct word or phrase that best fits each of the numbered blanks:   

There are several changes in the procedure for employees ___5___ wish to apply for vacant positions within the company. These changes make it much easier for in-house employees to fill vacancies that occur. First, __6__ most important difference is that employees will now be notified of all available positions before the positions are advertised for the general public. Accordingly, all in-house candidates will be interviewed before we see any out-side candidates, and we will offer the job to outside candidates only if no current employees are able to fill the position. Second, under the new procedure, in-house employees can be hired even if they don’t __7__ all job requirements. Under our old policy, in-house employees had to meet all job qualifications in order to obtain the vacant position. Now, however, employees who have proven themselves dedicated __8__ the company will be hired for a vacant position even if they are lacking some minor qualifications; training will be provided. A third change involves recommendations. Form now on, employees do not need to be recommended for an in-house position before they __9__. Instead, employees may apply as soon as they are aware of the vacancy. The remaining procedures and policies (those regarding increase in pay, interview procedure, and hiring approval) remain the same.

Question 8:

Hoà tan hoàn toàn 16 gam hỗn hợp Mg và Fe bằng dung dịch H2SO4 loãng 20% (vừa đủ). Sau phản ứng thấy khối lượng dung dịch tăng thêm 15,2 gam. Nồng độ % của MgSO4 có trong dung dịch sau phản ứng là  

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:

Cooperation is the common endeavor of two more people to perform a task of reach a jointly cherished goad. Like competition and conflict, there are different forms of cooperation, based on group organization and attitudes. In the first form, known as primary cooperation, group and individuals fuse. The group contains nearly all of each individual’s life. The rewards of the group’s work are share with each number. There is an interlocking identity of individual, group, and task performed. Means and goals become one, for cooperation itself is valued. While primary cooperation is most often characteristic of preliterate societies, secondary cooperation is characteristic of many modern societies. In secondary cooperation, individuals devote only part of their lives to the group. Cooperation itself is not a value. Most member of the group fell loyalty, but the welfare of the group is not the first consideration. Members perform tasks so that they can separately enjoy the fruits of their cooperation in the form of salary, prestige, or power. Business offices and professional athletic teams are example of secondary cooperation. In the third type, called tertiary cooperation or accommodation, latent conflict underlies the share work. The attitudes of the cooperation parties are purely opportunistic; the organization is loose and fragile. Accommodation involve common means cease to aid achieve antagonistic goals; it breaks when the common means cease to aid each party in reaching its goals. This is not, strictly speaking, cooperation at all, and hence the somewhat contradictory term antagonistic cooperation is sometimes used for this relationship.

Question: The word “fragile” in line 16 is closest in meaning to________         

Cho hỗn hợp gồm a mol Zn; b mol Mg vào dung dịch có chứa c mol AgNO3; d mol Cu(NO3)2 đến khi kết thúc phản ứng thu được dung dịch X, chất rắn Y. Biết rằng (0,5c < a + b < 0,5c + d) . Phát biểu nào sau đây đúng ?         

Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct word or phrase that best fits each of the numbered blanks from 24 to 28:

Few people now realize the reality of global warming and its effects on the world’s climate. Many scientists (24) _______ the blame for recent natural disasters on the increase in the world’s temperatures and are convinced that, more than ever before, the Earth is at (25) _______ from the forces of the wind, rain and sun. According to them, global warming is making extreme weather events, such as hurricanes and droughts, even more severe and causing sea levels all around the world to rise. Environmental groups are putting pressure on governments to take action to reduce the amount of carbon dioxide which is given (26) _______ by factories and power plants, thus attacking the problem at its source. They are in (27) _______ of more money being spent on research into solar, wind, and wave energy devices, which could then replace existing power (28) _______. Some scientists, however, believe that even if we stopped releasing carbon dioxide and other gases into the atmosphere tomorrow, we would have to wait several hundred years to notice the results. Global warming, it seems, is to stay.

Question 24:       

Cho m gam Mg vào dung dịch X gồm 0,03 mol Zn(NO3)2 và 0,05 mol Cu(NO3)2, sau một thời gian thu được 5,25 gam kim loại và dung dịch YCho dung dịch NaOH vào dd Y khối lượng kết tủa thu được là 6,67 gam. Giá trị của m là         

Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct word or phrase that best fits each of the numbered blanks from 24 to 28:

Few people now realize the reality of global warming and its effects on the world’s climate. Many scientists (24) _______ the blame for recent natural disasters on the increase in the world’s temperatures and are convinced that, more than ever before, the Earth is at (25) _______ from the forces of the wind, rain and sun. According to them, global warming is making extreme weather events, such as hurricanes and droughts, even more severe and causing sea levels all around the world to rise. Environmental groups are putting pressure on governments to take action to reduce the amount of carbon dioxide which is given (26) _______ by factories and power plants, thus attacking the problem at its source. They are in (27) _______ of more money being spent on research into solar, wind, and wave energy devices, which could then replace existing power (28) _______. Some scientists, however, believe that even if we stopped releasing carbon dioxide and other gases into the atmosphere tomorrow, we would have to wait several hundred years to notice the results. Global warming, it seems, is to stay.

Question 25:       

Hòa tan hoàn toàn 6,5 gam Zn bằng dung dịch H2SO4 loãng thu được V lít H2 (đktc). Giá trị của V là: