Hợp kim chứa nguyên tố X nhẹ và bền, dùng chế tạo vỏ máy bay, tên lửa. Nguyên tố X còn được sử dụng trong xây dựng, ngành điện và đồ gia dụng. Nguyên tử của nguyên tố X có tổng số hạt (proton, electron, neutron) là 40. Trong nguyên tử X, tổng số hạt mang điện nhiều hơn tổng số hạt không mang điện là 12.

Số proton và neutron trong X lần lượt là

Cho tam giác \(ABC\) có độ dài các cạnh là \(a\), \(b\) và \(c\). Mệnh đề nào sau đây đúng?

Mệnh đề nào là phủ định của mệnh đề: “\(\exists x \in \mathbb{R}|{x^2} - 3x + 2 > 0\)”?

Cho đoạn chương trình sau:

s=0

i=1

while i<=5:

s=s+1

i=i+1

Sau khi thực hiện đoạn chương trình trên giá trị của s là?

Cho tam giác \(ABC\) vuông tại \(A\), \(AC=b\), \(AB=c\). Lấy điểm \(M\) trên cạnh \(BC\) sao cho \(\widehat{BAM}={{30}^{\circ }}\). Tỉ số \(\frac{MB}{MC}\) bằng

Đối với điện trở màu, vòng màu thứ 2 chỉ:

Tình trạng người thiếu dinh dưỡng chủ yếu tập trung ở châu lục nào?

Bệnh vàng lá gân xanh hại cam:

Tổ chức nào sau đây không phải là biểu hiện của xu thế toàn cầu hóa?

Thị trường gạo, thị trường cà phê, thị trường thép thuộc cách phân loại nào của thị trường?

Quá trình lên men được ứng dụng trong bao nhiêu hoạt động sau đây?

1. Sản xuất rượu bia

2. Làm sữa chua

3. Muối dưa

4. Sản xuất giấm 

Read the passage carefully. Choose an option (A, B, C or D) that best answers each question from 23 to 30.

1. How do children learn about wildlife? And is what they learn the sort of thing they should be learning? It is my belief that children should not just be acquiring knowledge of animals but also developing attitudes and feelings towards them based on exposure to the real lives of animals in their natural habitats. But is this happening?

2. Some research in this area indicates that it is not. Learning about animals in school is often completely disconnected from the real lives of real animals, with the result that children often end up with little or no understanding or lasting knowledge of them. They learn factual information about animals, aimed at enabling them to identify them and have various abstract ideas about them, but that is the extent of their learning. Children's storybooks tend to personify animals as characters rather than teach about them.

3. For direct contact with wild and international animals, the only opportunity most children have is visiting a zoo. The educational benefit of this for children is often given as the main reason for doing it but research has shown that zoo visits seldom add to children's knowledge of animals – the animals are simply like exhibits in a museum that the children look at without engaging with them as living creatures. Children who belong to wildlife or environmental organizations or who watch wildlife TV programmes, however, show significantly higher knowledge than any other group of children studied in research. The studies show that if children learn about animals in their natural habitats, particularly through wildlife-based activities, they know more about them than they do as a result of visiting zoos or learning about them in the classroom.

4. Research has also been done into the attitudes of children towards animals. It shows that in general terms, children form strong attachments to individual animals, usually their pets, but do not have strong feelings for animals in general. This attitude is the norm regardless of the amount or kind of learning about animals they have at school. However, those children who watch television wildlife programs show an interest in and affection for wildlife in its natural environment, and their regard for animals in general is higher.

What could be the best title for the passage?

Ý kiến nào sau đây là sai khi bàn về vấn đề cạnh tranh không lành mạnh?

Trong không gian Oxyz, cho các điểm \(A(1;1;2)\) và \(B(4;5;1)\). Các điểm M, N di động trên mặt phẳng \((Oxy)\) sao cho \(MN=1\). Tổng \(AM+BN\) có giá trị nhỏ nhất là bao nhiêu (nhập đáp án vào ô trống)?

Cho cấu trúc nguyên tử aluminium theo mô hình Rutherford – Bohr như sau:

Lớp ngoài cùng của nguyên tử aluminium có bao nhiêu electron?

Hàm số nào dưới đây không phải là hàm số lôgarit?  

Công nghệ nào sau đây được phân loại theo đối tượng áp dụng?

Chọn phát biểu sai trong các phát biểu phía dưới?

Chọn đáp án đúng về chuyển động. 

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

            For many people who live in cities, parks are an important part of the landscape. They provide a place for people to relax and play sports, as well as a refuge from the often harsh environment of a city. What people often overlook is that parks also provide considerable environmental benefits.

            One benefit of parks is that plants absorb carbon dioxide - a key pollutant - and emit oxygen, which humans need to breathe. According to one study, an acre of trees can absorb the same amount of carbon dioxide that a typical car emits in 11,000 miles of driving. Parks also make cities cooler. Scientists have long noted what is called the Urban Heat Island Effect: building materials such as metal, concrete, and asphalt absorb much more of the sun’s heat and release it much more quickly than organic surfaces like trees and grass. Because city landscapes contain so much of these building materials, cities are usually warmer than surrounding rural areas. Parks and other green spaces help to mitigate the Urban Heat Island Effect.

            Unfortunately, many cities cannot easily create more parks because most land is already being used for buildings, roads, parking lots, and other essential parts of the urban environment. However, cities could benefit from many of the positive effects of parks by encouraging citizens to create another type of green space: rooftop gardens. While most people would not think of starting a garden on their roof, human beings have been planting gardens on rooftops for thousands of years. Some rooftop gardens are very complex and require complicated engineering, but others are simple container gardens that anyone can create with the investment of a few hundred dollars and a few hours of work.

            Rooftop gardens provide many of the same benefits as other urban park and garden spaces, but without taking up the much-needed land. Like parks, rooftop gardens help to replace carbon dioxide in the air with nourishing oxygen. They also help to lessen the Urban Heat Island Effect, which can save people money.

            In the summer, rooftop gardens prevent buildings from absorbing heat from the sun, which can significantly reduce cooling bills. In the winter, gardens help hold in the heat that materials like brick and concrete radiate so quickly, leading to savings on heating bills. Rooftop vegetable and herb gardens can also provide fresh food for city dwellers, saving them money and making their diets healthier. Rooftop gardens are not only something everyone can enjoy, they are also a smart environmental investment.

Question 40: According to the author, one advantage that rooftop gardens have over parks is that they______.

Đọc đoạn trích sau:

(1) “Sao anh không về chơi thôn Vĩ?

(2) Nhìn nắng hàng cau nắng mới lên

(3) Vườn ai mướt quá xanh như ngọc

(4) Lá trúc che ngang mặt chữ điền.

(5) Gió theo lối gió mây đường mây

(6) Dòng nước buồn thiu hoa bắp lay

(7) Thuyền ai đậu bến sông trăng đó

(8) Có chở trăng về kịp tối nay?”

(Hàn Mặc Tử, Đây thôn Vĩ Dạ, Ngữ văn 11, tập hai, NXB Giáo dục Việt Nam, 2019)

Phương thức biểu đạt chính ở khổ thơ đầu tiên của đoạn trích là gì?