Hòa tan hoàn toàn 16,4 gam hỗn hợp X chứa Mg, MgO và Fe₃O₄ (trong X oxi chiếm 22,439% về khối lượng) bằng dung dịch chứa HNO₃ và 0,835 mol HCl thu được dung dịch Y chỉ chứa hỗn hợp 3 muối và 0,05 mol khí NO (duy nhất). Phần trăm khối lượng của Mg trong X gần nhất với: 

A. 26%

B. 29%

C. 22%

D. 24%

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

If parents bring up a child with the sole aim of turning the child into a genius, they will cause a disaster. According to several leading educational psychologists, this is one of the biggest mistakes, which ambitious parents make. Generally, the child will be only too aware of what his parents expect, and will fail. Unrealistic parental expectations can cause great damage to children.

            However, if parents are not too unrealistic about what they expect their children to do, but are ambitious in a sensible way, the child may succeed in doing very well – especially if the parents are very supportive of their child. Michael Collins is very lucky. He is crazy about music, and his parents help him a lot by taking him to concerts and arranging private piano and violin lessons for him. They even drive him 50 kilometers twice a week for violin lessons. Michael’s mother knows very little about music, but his father plays the trumpet in a large orchestra. However, he never makes Michael enter music competitions if he is unwilling.

            Winston Smith, Michael’s friend, however, is not so lucky. Both his parents are successful musicians, and they set too high a standard for Winston. They want their son to be as successful as they are and so they enter him for every piano competition held. They are very unhappy when he does not win. Winston is always afraid that he will disappoint his parents and now he always seems quiet and unhappy.

Who have criticized the methods of some ambitious parents? 

A. Successful musician.

B. Unrealistic parents.

C. Their children.

D. Educational psychologists.

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

We shouldn’t use too many plastic bags because they are very hard to ___________.

A. dissolve

B. melt

C. heat

D. soften

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

       Before photography was invented in 1839, painted portraits, and engravings based on them, were one of the few ways to record likenesses. From the Colonial era through the 1820s, portraiture was the most widely practiced genre of American art, and it continued to be a significant form through the 19th century. The demand for likenesses was incessant, and portraiture was often the primary source of income for artists. Artists frequently made portraits of famous people to attract interest and potential patrons. For example, in 1834 Chester Harding painted frontiersman Davy Crockett, then a member of the U.S. House of Representatives, for display in hisBostongallery.

       A consistent belief through most of the 18th and 19th centuries was that character could be read from a person's face, or the bumps on his or her head, or from facial expressions, and that portraits should convey these indicators of character. These theories of physiognomy and phrenology have since been debunked, but they were important considerations in depicting the nation's leaders, since such portraits were often made for posterity. Most people had only one portrait painted in their lifetime, if at all, so artists were selected with great care, and expectations were high.

       Before the 1840s, American portraiture was influenced primarily by English techniques, poses, compositions and gestures, and many artists received at least part of their training inEngland. Even canvas sizes followed the British example. Portraits made on commission were priced according to canvas size and the materials and labor involved.

            In the late 19th century as European portraitists began traveling to the United States to acquire commissions from the growing upper class, American artists increasingly felt they needed to train abroad in order to succeed at home. Paris continued to be the main lure as painters such as Eakins, Whistler, Beaux and Sargent went to study there. Some of America's best-known portraitists, in fact, became expatriates.

In what ways did American artists try to gain greater success?

A. by inviting European artists to America

B. by traveling abroad for training

C. by not only painting portraits

D.  by becoming expatriates