Khó khăn chủ yếu về mặt kinh tế - xã hội của Bắc Trung Bộ là

Ý nào dưới đây không phải là vai trò của quá trình hô hấp đối với cơ thể thực vật?

Choose A, B, C or D to answer each question.

Which of the following situations best exemplifies “caution” where someone takes care in order to avoid danger or mistakes?

Một vật chịu tác động của hai lực bao gồm $\overrightarrow{F_1}$ theo phương $\overrightarrow{MA}$ tạo với phương nằm ngang một góc 60° và $\overrightarrow{F_2}$ theo phương $\overrightarrow{MB}$ nằm ngang. Vật di chuyển được một đoạn 4 m theo phương ngang từ M. Hai lực $\overrightarrow{F_1}$ và $\overrightarrow{F_2}$ có cùng độ lớn bằng 10 N. Công sinh bởi hợp lực của $\overrightarrow{F_1}$ và $\overrightarrow{F_2}$ có độ lớn bằng bao nhiêu?

Cho hai đường thẳng \(d_{1}: m x+y=m+1\) và \(d_{2}: x+m y=2\).

Khi \(m=2\), góc giữa hai đường thẳng xấp xỉ bằng:

Kí hiệu cây có tán là:

a. One useful suggestion is to reduce the use of private cars and choose public transport instead, which helps to lower air pollution and decrease traffic problems in cities.

b. In the long term, following such suggestions can lead to a more sustainable and responsible way of living.

c. These actions not only protect the planet but also create cleaner and healthier communities for people.

d. Another effective idea is to recycle materials such as paper, glass, and plastic, so that natural resources are saved and less waste is produced.

e. Improving the environment requires small but important changes in daily life.

Tài nguyên khoáng sản đa dạng ở khu vực Mỹ Latinh là cơ sở để phát triển ngành gì?

Read the passage below and choose A, B, C or D.

Although noise, commonly defined as unwanted sound, is a widely recognized form of pollution, it is very difficult to measure because the discomfort experienced by different individuals is highly subjective and, therefore, variable. Exposure to lower levels of noise may be slightly irritating, whereas exposure to higher levels may actually cause hearing loss. Particularly in congested urban areas, the noise produced as a by-product of our advancing technology causes physical and psychological harm, and detracts from the quality of life for those who are exposed to it.

Unlike the eyes, which can be covered by the eyelids against strong light, the ear has no lid, and is, therefore, always open and vulnerable; noise penetrates without protection. Noise causes effects that the hearer cannot control and to which the body never becomes  accustomed. Loud noises instinctively signal danger to any organism with a hearing mechanism, including human beings. In response, heartbeat and respiration accelerate, blood vessels constrict, the skin pales, and muscles tense. In fact, there is a general increase in functioning brought about by the flow of adrenaline released in response to fear, and some of these responses persist even longer than the noise, occasionally as long as thirty minutes after the sound has ceased.

Because noise is unavoidable in a complex, industrial society, we are constantly responding in the same way that we would respond to danger. Recently, researchers have concluded that noise and our response may be much more than an annoyance. It may be a serious threat to physical and psychological health and well-being, causing damage not only to the ear and brain but also to the heart and stomach. We have long known that hearing loss is America's number one nonfatal health problem, but now we are learning that some of us with heart disease and ulcers may be victims of noise as well. Fetuses exposed to noise tend to be overactive, they cry easily, and they are more sensitive to gastrointestinal problems after birth. In addition, the psychic effect of noise is very important. Nervousness, irritability, tension, and anxiety increase affecting the quality of rest during sleep, and the efficiency of activities during waking hours, as well as the way that we interact with each other.

Which of the following statements would the author most likely support?

Có bao nhiêu số gồm 3 chữ số khác nhau được thành lập từ các chữ số 0, 2, 4, 6, 8 ? 

Một thanh đồng chất có chiều dài L, trọng lượng 200 N, treo một vật có trọng lượng 450 N vào thanh như Hình 21.2. Các lực \(\overrightarrow {{F_1}} ,\overrightarrow {{F_2}} \) của thanh tác dụng lên hai điểm tựa có độ lớn lần lượt là

Trong chân không, sóng điện từ truyền đi với tốc độ là

Choose A, B, C or D: Remember that things such as language, food and clothing are simply expressions of our cultural______.