Chọn ý đúng: Phát minh nào cho phép con người lưu giữ và truyền thông tin chính xác hơn?

Ngành Sinh học bao gồm những lĩnh vực nghiên cứu nào?

Hợp chất nào dưới đây tạo được liên kết hydrogen liên phân tử?

Nội dung nào sau đây là một trong những vai trò của lịch sử và văn hóa đối với sự phát triển ngành du lịch?

Đâu là ý đúng: Có mấy tiêu chí trong đánh giá công nghệ?

Hòa tan \(\text23,2\) gam một mẫu quặng magnetite (chỉ chứa \(\text{F}{{\text{e}}_{3}}{{\text{O}}_{4}}\) và tạp chất trơ) bằng dung dịch sulfuric acid loãng dư. Lọc bỏ tạp chất không tan, thêm nước cất vào dịch lọc, thu được \(200\text{ }\!\!~\!\!\text{ mL}\) dung dịch X. Để chuẩn độ \(5\text{ }\!\!~\!\!\text{ mL}\) dung dịch X cần dùng \(17,5\text{ }\!\!~\!\!\text{ mL}\) dung dịch \(\text{KMn}{{\text{O}}_{4}}0,02\text{M}\). Phần trăm khối lượng của \(\text{F}{{\text{e}}_{3}}{{\text{O}}_{4}}\) trong mẫu quặng magnetite xấp xỉ là:

Đường thẳng nào vuông góc với đường thẳng \(y = \sqrt 7 x + 3\)?

Nguyên nhân nào dẫn đến đời sống của nông dân Việt Nam này càng bần cùng trong những năm Chiến tranh thế giới thứ nhất?

Phần tô màu (không bao gồm đường thẳng) trong hình vẽ là miền nghiệm của bất phương trình nào sau đây?

Đặc trưng nào dưới đây phân biệt sự khác nhau giữa pháp luật và các loại quy phạm xã hội khác?

Nhiệm vụ của cơ cấu trục khuỷu, thanh truyền là gì?

You are attending a friend’s birthday party where many of his friends are playing a lively game with balloons. You are quite shy and don’t know those friends However, you want to be part of the game. What can you say to play the game?

Phát biểu nào sai khi nói về quá trình lên men?

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the best answer to each of the following questions from 31 to 40.

Biting into a ripe, juicy fruit brings a smile to many people’s faces. But eating that same fruit a week before it is ripe probably wouldn’t be as enjoyable! Unripe fruits are often hard and bitter, but that serves a purpose. The hard exterior of an unripe fruit protects the developing seed inside. After a seed fully develops inside the fruit, the fruit changes color, softens, and gets sweeter to become more attractive to animals and humans. These organisms eat the fruit and spread its seeds, ensuring the plant’s survival and regrowth.

But how does a fruit ripen? The ripening process involves many complex chemical reactions. When a fruit ripens, it goes through a chemical change. A chemical change happens when bonds within molecules break, and the atoms that once formed them regroup into new molecules. Chemical changes are irreversible. Once a fruit ripens, it cannot become unripe again.

One molecule responsible for this chemical change is ethylene. Ethylene (C2H4) is a colorless gas made up of carbon and hydrogen atoms. (I). It is a naturally occurring molecule in the atmosphere. (II). It is also an important plant hormone. (III). Plants release ethylene through the growing tips of roots, flowers, and ripening fruit. (IV). Although ethylene serves other purposes in plants, one of its main purposes is to trigger the chemical reactions that cause fruits to ripen. As the fruit matures, oxygen in the air helps stimulate the production of ethylene. This ethylene production is a signal that begins fruit ripening. For that reason, unripe fruits have low levels of ethylene, while ripe fruits have higher levels of ethylene. Most fruits produce ethylene and respond to ethylene in the atmosphere.

Although fruits require ethylene to ripen, different types of fruits respond to this molecule in two distinct ways: non-climacteric fruits and climacteric fruits. Non-climacteric fruits do not ripen after harvesting. They produce very little ethylene of their own. Climacteric fruits, on the other hand, continue to ripen after they are picked. These fruits produce a large amount of ethylene. Climacteric fruits can also speed up the ripening process of other fruits nearby since they release high levels of ethylene into the air.  

The phrase made up of in paragraph 3 could best be replaced by:

Chọn những phát biểu đúng về AO.

Read the following passage about the impact of social media on mental health and mark the letter A, B, C, or D on your answer sheet to indicate the best answer to each of the following questions from 31 to 40.

[I] In recent years, social media platforms have become a central part of daily life, offering users countless ways to connect, share, and communicate. [II] While these platforms offer many advantages, experts have noted rising concerns about their effects on mental health, particularly among young people (Smith & Anderson, 2018). [III] Studies reveal that excessive social media use can contribute to feelings of anxiety, depression, and loneliness, despite its intention to promote connection and social interaction (Twenge & Campbell, 2019). [IV]

A primary reason for these mental health concerns is the tendency for social media users to compare themselves to others. Platforms like Instagram and Facebook often highlight idealized lifestyles, leading users to feel inadequate about their own lives. Additionally, the constant notifications and messages contribute to a "fear of missing out," or FOMO, which keeps individuals in a cycle of checking their phones, often reducing the quality of sleep and overall well-being.

There is also a growing body of research suggesting a link between social media use and decreased attention spans. When users frequently switch between apps and notifications, their ability to focus for extended periods may diminish (Rosen, 2019). This shift in attention can interfere with productivity, especially in academic and professional settings, where sustained focus is essential.

Addressing these challenges requires a multi-faceted approach. Some mental health professionals suggest limiting screen time and setting boundaries, such as "device-free" hours before bedtime. Others recommend engaging in offline activities, like reading or exercising, to reduce dependence on social media and build healthier habits. According to psychologists, such strategies can enhance mental resilience and allow for more meaningful, balanced relationships (Robinson & Smith, 2020).

Which of the following is TRUE according to the passage?

Hoạt động tiêu dùng bao gồm mấy loại chính?

Anh và Pháp phải chịu một phần trách nhiệm về sự bùng nổ cuộc Chiến tranh thế giới thứ hai (1939 - 1945) vì:

Nhiệt tạo thành chuẩn của chất nào dưới đây có giá trị bằng 0?

Read the passage and mark the letter A, B, C or D to answer the following questions.
Volunteering offers many of the same social benefits, with the added bonus of helping others and developing useful skills to put on your CV. Plus, students are in a unique position to help, suggests Tom Fox. "They can take their enthusiasm and excitement for opportunities and share their passions, subject knowledge and experience with people." The idea of giving up time for nothing might seem impractical at first, especially once the pressures of study and coursework or exams begin to mount up. However, Michelle Wright, CEO of charity support organization Cause4, suggests seeing volunteering as a two-way street. "I think it is fine for undergraduates to approach volunteering as a symbiotic relationship where doing good is just one part of the motivation for reaching personal and professional goals."
Katerina Rudiger, head of skills and policy campaigns at the Chartered Institute of Personnel and Development (CIPD), says: "Volunteering can be a valuable way of gaining that experience, as well as building confidence, broadening your horizons, becoming a better team player and developing those all- important 'employability skills' such as communication and decision making." Amanda Haig, graduate HR manager, agrees that volunteering can help your employment prospects. "Volunteering can demonstrate positive personality traits and skill sets, such as proactivity, and teamwork," she says.
A positive side-effect of volunteering is improving your time at university by getting involved in the local community. Leaving the student bubble can make your time as an undergraduate much more varied. At Bath Spa University, more than 1,000 students volunteered over the past year, doing everything from working on local environmental projects to helping in schools or assisting the elderly. ”Quite often there can be a divide between students and permanent residents," says students' union president Amy Dawson, "but if students invest a little time now, they will be giving something back to the local community and will reap the benefits in the future."
“You might also find that volunteering helps your studies if you choose the right program. At Lancaster, volunteering is linked into academic modules in some cases", explains Fox. "This has multiple wins. Students get to apply their learning in the classroom and share their interests with children in local schools or community organizations, while schools gain skilled students with a passion for a subject that enthuses their pupils."

What does the word "they" refer to in paragraph 3?

Mark the letter A, B, C, or D on your answer sheet to indicate the word whose underlined part differs from the other three in pronunciation in each of the following questions.: digestion suggestion question attraction