Read the following passage and mark the letter A, B, tr or I) to indicate the correct answer to each of the questions from 36 to 42.

Humans have struggled against weeds since the beginnings of agriculture. Marring our gardens is one of the milder effects of weeds - any plants that thrive where they are unwanted. They clog waterways, destroy wildlife habitats, and impede fanning. Their spread eliminates grazing areas and accounts for one-third of all crop loss. They compete for sunlight, nutrients, and water with useful plants.

The global need for weed control had been answered mainly by the chemical industry. Its herbicides are effective and sometimes necessary, but some pose serious problems, particularly if misused. Toxic compounds threaten animal and public health when they accumulate in food plants, groundwater, and drinking water. They also harm workers who apply them.

In recent years, the chemical industry has introduced several herbicides that are more ecologically sound. Yet new chemicals alone cannot solve the world's weed problems. Hence, scientists are exploring the innate weed-killing powers of living organisms, primarily insects and microorganisms.

The biological agents now in use are environmentally benign and are harmless to humans. They can be chosen for their ability to attack selected targets and leave crops and other plants untouched. In contrast, some of the most effective chemicals kill virtually all the plants they come in contact with, sparing only those that are naturally resistant or have been genetically modified for resistance. Furthermore, a number of biological agents can be administered only once, after which no added applications are needed. Chemicals typically must be used several times per growing season.

Which of the following terms does the author define in the first paragraph?

A. weeds

B. nutrients 

C. wildlife habitats 

D. grazing area

Read the following passage and mark the letter A, B, C or D to indicate the correct word or phrase that best fits each of the numbered blanks from 31 to 35.

One of the hottest topics on the international development agenda is how to harness the power of International Monetary Fund for the benefit of developing countries. What is sometimes called "the death of distance", brought about by the Internet, allow professional services such as (31) _________ education and training to be provided easily and quickly to (32) _____ areas. Some of the gains can be seen in countries as diverse as India and Morocco, where innovations range from (33)______ government announcements to local craftsmen selling their wares to a (34)            _______ market. But already a huge and expanding digital divide is opening up between developed and developing nations. The major tasks facing world leaders at present is to supply everybody on the planet with clean water, basic education and the drugs needed to fight preventable diseases. Installing a modem in every classroom and linking us to (35) _______ _____  must be a lesser criteria at least.

Điền vào ô 32.

A. secluded

B. far 

C. remote

D. uninhabited

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.

Chứng minh rằng số gồm 27 chữ số 1 thì chia hết cho 27

Cho phép tính:

Số cần điền vào chỗ trống là:

Để khử hoàn toàn 3,04 gam hỗn hợp X gồm FeO, Fe 3 O 4 ,   Fe 2 O 3 cần 0,05 mol H 2 . Mặt khác hoà tan hoàn toàn 3,04 gam hỗn hợp X trong dung dịch H 2 SO 4 đặc nóng thì thu được thể tích V ml  SO 2 (đktc). Giá trị V(ml) là

A. 112 ml  

B. 224 ml      

C. 336  ml  

D. 448 ml