Cho thứ tự sắp xếp một số cặp oxi hoá - khử của kim loại trong dãy điện hoá:

Mg²⁺/Mg; Zn²⁺/Zn; Pb²⁺/Pb; Hg²⁺/Hg.

Ion kim loại có tính oxi hoá yếu nhất trong dãy là   

Trường hợp nào sau đây lực tác dụng vào một vật có trục quay cố định mà không làm cho vật quay?

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.

Which of the following is NOT true according to the passage?

Phát biểu nào sau đây là sai khi nói về sóng điện từ?

Miền Nam Trung Bộ và Nam Bộ của nước ta có lợi thế mạnh mẽ trong phát triển loại cây nào sau đây?

Vì sao ta có thể lập mối quan hệ giữa hai trường của hai bảng nhưng Access lại không chấp nhận?

Read the following leaflet and mark the letter A, B, C or D on your answer sheet to indicate the option that bestfits each of the numbered blanks from 7 to 12.

Join Our Student Exchange Program!

Are you eager to explore a new culture, improve your language skills, and make lifelong friends? Our Student Exchange Program is the perfect opportunity for you!

Students from our school will have the chance to study abroad while welcoming (7) ______ students into their homes. This is a great way to experience different educational systems and lifestyles.

During the program, you will (8) ______ new challenges, such as adapting to a new environment and communicating in a foreign language. (9) ______, these experiences will help you grow both academically and personally.

Participants will receive full (10) ______, including accommodation, meals, and tuition fees.

Instead of traveling as a tourist, why not become a local for a semester? This exchange allows you to fully immerse yourself in a new culture.

This program helps students develop essential skills such as independence, adaptability, and (11) ______.

Apply now and take the first step towards an unforgettable experience in international (12) ______!

Xác định lỗi SAI trong câu văn sau:

“Phan Bội Châu đã dùng ngòi bút của mình để tố cáo sự dã man của thực dân Pháp nhưng ông đã kêu gọi thực hiện nhiều hoạt động đấu tranh. ”

Cho cấp số cộng $(u_n)$ có số hạng đầu $u_1=\sqrt{2}$ và công sai $d=3\sqrt{2}$. Số hạng thứ năm của cấp số cộng đó là

Khoảng thời gian giữa hai lần lấy mẫu được gọi là

Cho \(F(x) = 3x^2 +1\) và \(G(x)=4x^2+2x\) lần lượt là nguyên hàm của \(f(x)\) và \(g(x)\). Xét \(H (x)\) là một nguyên hàm của hàm số \(h(x) = f(x)g(x)\). Phương án nào dưới đây đúng?

Trong Python, câu lệnh nào là dùng để đưa dữ liệu ra màn hình?

Hệ thống chính trị Việt Nam được tổ chức và hoạt động theo mấy nguyên tắc cơ bản?