ABC đều. Gọi D,E,F là 3 điểm lần lượt nằm trên các cạnh AB, BC, CA sao cho AD=BE=CF a) Chứng minh rằng DEF là tam giác đều b) Gọi M, N, K là 3 điểm lần lượt nằm trên các tia đối của các tia AB, BC,CA sao cho AM=BN=CK Chứng minh  là tam giác đều

Read the following andmark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 22 to 29.

Harvard University, today recognized as part of the top echelon of the world's universities, came from very inauspicious and humble beginning.

This oldest of American universities was founded in 1636, just sixteen years after the Pilgrims landed at Plymouth. Included in the Puritan emigrants to the Massachusetts colony during this period were more than 100 graduates of England's prestigious Oxford and Cambridge universities, and these universities graduates in the New Word were determined that their sons would have the same educational opportunities that they themselves had had. Because of this support in the colony for an institution of higher learning, the General

Court of Massachusetts appropriated 400 pounds for a college in October of 1636 and early the following year decided on a parcel of land for the school; this land was in an area called Newetowne, which was later renamed Cambridge after its English cousin and is the site of the present-day university.

When a young minister named John Harvard, who came from the neighboring town of Charlestowne, died from tuberculosis in 1638, he willed half of his estate of 1,700 pounds to the fledgling college. In spite of the fact that only half of the bequest was actually paid, the General Court named the college after the minister in appreciation for what he had done. The amount of the bequest may not have been large, particularly by today's standard, but it was more than the General Court had found it necessary to appropriate in order to open the college.

Henry Dunster was appointed the first president of Harvard in 1640, and it should be noted that in addition to serving as president, he was also the entire faculty, with an entering freshmen class of four students. Although the staff did expand somewhat, for the first century of its existence the entire teaching staff consisted of the president and three or four tutors

The pronoun "they" in the second paragraph refers to ______________

A. son

B. university graduates

C. Oxford and Cambridge universities 

D. educational opportunities

Mark the letter A, B, C or D to indicate the sentence that is closest in meaning to each of the following questions.

"I am sorry, Jean. I broke your bicycle," said John.

A. John apologized Jean for breaking her bicycle

B. John apologized Jean for having broken her bicycle

C. John apologized to Jean to have broken her bicycle

D. John apologized to Jean for having broken her bicycle

Read the following pasage and mark the letter A. B, C or D on your answer sheet to indicate the correct answer to each of the questions from 41 to 48.

Another critical factor that plays a part in susceptibility to colds is age. A study done by the University of Michigan School of Public Health revealed particulars that seem to hold true for the general population. Infants are the most cold-ridden group, averaging more than six colds in their first year. Boys have more colds than girls up to age three. After the age of three, girls are more susceptible than boy's , and teenege girls average three colds a year to boy’s two.

The general incidence of continues to decline into maturity. Elderly people who are in good health have as few as one or two colds annually. One exception is founds among people in the twentics, especially women, who show a rise in cold infections, because people in this age group are most likely to have young children. Adults who delay having children until thirties forties experience the same sudden increase in cold infections.

The study also found that economics play an important role. As income increases, the frequency at which are reported in the family decreases. Families with the lowest income suffer about a third more colds than families at the lower end. Lower income generally forces people to live in more cramped quarters than those typically occupied by wealthier by wealthier people, and crowding increses the opportunities for the cold virus totravel from person to person. Low income may also adversely influence diet. The degree to which poor nutrition affects susceptibility to colds is not yet clearly established, but an inadequate diet is suspected of lowering resistance generally.

(source: TOEFL reading)

It maybe inferred from the passage that which of the following groups of people is most likely to catch colds?

A. infant boys

B. oung girls

C. teenage boys

D. elderly women

Khi khởi động xe máy, không nên nhấn nút khởi động quá lâu và nhiều lần liên tục vì

A. dòng đoản mạch kéo dài sẽ làm hỏng acquy.

B. tiêu hao quá nhiều năng lượng.

C. động cơ đề  sẽ rất nhanh hỏng.

D. hỏng nút khởi động.

Số 1993 có phải là tổng của 3 số tự nhiên liên tiếp không?

Trong giải cầu lông kỷ niệm ngày truyền thống học sinh sinh viên có 8 người tham gia trong đó có hai bạn Việt và Nam. Các vận động viên được chia làm hai bảng A và B, mỗi bảng gồm 4 người. Giả sử việc chia bảng thực hiện bằng cách bốc thăm ngẫu nhiên. Tính xác suất để cả hai bạn Việt và Nam nằm chung một bảng đấu.

A. 3 5

B.  3 7

C.  3 11

D.  3 13

Chữ số thích hợp viết vào ô trống để được số có 3 chữ số 35... chia hết cho 2 và 5 là:

A. 5

B. 0

C. 2

D. 7