1.is reading

2.is'n listening

3.is coming

I spend two hour getting to Ha Noi

X là este đơn chức, không no chứa một liên kết đôi C=C, Y là este no, hai chức (X, Y đều mạch hở). Đốt cháy hoàn toàn 23,16 gam hỗn hợp E chứa X, Y cần dùng 0,96 mol O₂. Mặc khác, đun nóng 23,16 gam hỗn hợp E cần dùng 330 ml dung dịch NaOH 1M, thu được một ancol duy nhất và hỗn hợp chứa a gam muối A và b gam muối B (M_A > M_B). Tỉ lệ gần nhất của a : b là

A. 1,6.

B. 0,8.

C. 1,1.

D. 1,3.

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

Very few people in the modern world obtain their food supply by hunting and gathering in the natural environment surrounding their homes. This method of harvesting from nature’s provision is the oldest known subsistence strategy and has been practiced for at least the last two million years. It was, indeed, the only way to obtain food until rudimentary farming and the domestication of wild animals were introduced about 10,000 years ago.

Because hunter-gatherers have fared poorly in comparison with their agricultural cousins, their numbers have dwindled, and they have been forced to live in marginal environments, such as deserts and arctic wastelands. In higher latitudes, the shorter growing seasons have restricted the availability of plant life. Such conditions have caused a greater dependence on hunting, and on fishing along the coasts and waterways. The abundance of vegetation in the lower latitudes of the tropics, on the other hand, has provided a greater opportunity for gathering a variety of plants. In short, the environmental differences have restricted the diet and have limited possibilities for the development of subsistence societies.

Contemporary hunter-gatherers may help us understand our prehistoric ancestors. We know from the observation of modern hunter- gatherers in both Africa and Alaska that a society based on hunting and gathering must be very mobile. While the entire community camps in a central location, a smaller party harvests the food within a reasonable distance from the camp. When the food in the area has become exhausted, the community moves on to exploit another site. We also notice seasonal migration patterns evolving for most hunter-gatherers, along with a strict division of labor between the sexes. These patterns of behavior may be similar to those practiced by mankind during the Paleolithic Period.

Question 68:According to the passage, which of the following is NOT mentioned?

A.   Harvesting from the natural environment had existed long before farming was taken up.

B.   Hunting or fishing develops where there are no or short growing seasons.

C.   The number of hunter-gatherers decreases where farming is convenient.

D.   The environmental differences produce no effect on subsistence societies.