Các phát biểu dưới đây là đúng hay sai khi nói về vai trò của sinh học trong cuộc sống?

Có mô hình trồng trọt công nghệ cao?

Phương trình \(\text{tan}x=\text{tan}\alpha \) có nghiệm là

Một khối kim loại nặng 3 kg được nung nóng bởi lò nung có công suất 210 W trong 5 phút thì nhiệt độ của khối kim loại tăng từ 20 ^oC lên 50 ^oC. Bỏ qua hao phí của lò nung. Trong các phát biểu dưới đây, phát biểu nào là đúng, phát biểu nào là sai?

Read the passage carefully. Choose an option (A, B, C, or D) that best answers each question from to 646 to 650:

1. Millions of people are using cellphones today. In many places, it is actually considered unusual not to use one. In many countries, cellphones are very popular with young people. They find that the phones are more than a means of communication - having a mobile phone shows that they are cool and connected.

2. The explosion in mobile phone use around the world has made some health professionals worried. Some doctors are concerned that in the future many people may suffer health problems from the use of mobile phones. In England, there has been a serious debate about this issue. Mobile phone companies are worried about the negative publicity of such ideas. They say that there is no proof that mobile phones are bad for your health.

3. On the other hand, medical studies have shown changes in the brain cells of some people who use mobile phones. Signs of change in the tissues of the brain and head can be detected with modern scanning equipment. In one case, a traveling salesman had to retire at young age because of serious memory loss. He couldn't remember even simple tasks. He would often forget the name of his own son. This man used to talk on his mobile phone for about six hours a day, every day of his working week, for a couple of years. His family doctor blamed his mobile phone use, but his employer's doctor didn't  agree.

4. What is it that makes mobile phones potentially harmful? The answer is radiation. High-tech machines can detect very small amounts of radiation from mobile phones. Mobile phone companies agree that there is some radiation, but they say the amount is too small to worry about.

5. As the discussion about their safety continues, it appears that it's best to use mobile phones less often. Use your regular phone if you want to talk for a long time. Use your mobile phone only when you really need it. Mobile phones can be very useful and convenient, especially in emergencies. In the future, mobile phones may have a warning label that says they are bad for your health. So for now, it's wise not to use your mobile phone too often.

What does the word “they” in paragraph 2 refer to?

Loại tài nguyên nào sau đây thuộc nhóm tài nguyên thiên nhiên vô hạn?

Dao động tổng hợp của một vật là tổng hợp của hai dao động cùng phương có phương trình lần lượt là $x_1=3\cos (10t+\frac{\pi }{2})$ và $x_2=A_2\cos (10t-\frac{\pi }{6})$(A2 > 0, t tính bằng giây). Tại t = 0, gia tốc của vật có độ lớn là $150\sqrt{3}$ cm/s². Biên độ dao động là

Con hãy lựa chọn đáp án Đúng hoặc Sai

Nội dung dưới đây đúng hay sai?

     “Huấn Cao ý thức được tài năng của mình, trừ chỗ tri kỉ, ông ít chịu cho chữ. Cả cuộc đời mới cho chữ ba người bạn, không vì vàng ngọc hay quyền thế mà ép mình cho chữ ai bao giờ”

Công của lực điện trường dịch chuyển một điện tích 5.10^-6 C dọc theo chiều một đường sức trong một điện trường đều 1000 V/m trên quãng đường dài 0,5 m là

Ý nào dưới đây không phải nhược điểm của cơ chế thị trường?

Bệnh tai xanh ở lợn lây nhiễm:

Đặt điện áp $u=U_{0}c\text{os}(100\pi t+\frac{\pi }{4})\left(V\right)$ vào hai đầu đoạn mạch chỉ có tụ điện thì cường độ dòng điện trong mạch là $i=I_{0}c\text{os}(100\pi t+\phi )\left(A\right)$. Giá trị của $\phi$ bằng:

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

[I] Social media has become a dominant force in modern communication, offering a range of benefits and challenges. [II] It has revolutionized the way people interact, share information, and even form relationships. [III] While these platforms offer opportunities for connection and expression, they also have their drawbacks. [IV] For instance, excessive use of social media has been linked to a range of negative effects, including mental health issues, social isolation, and decreased productivity. [V] However, when used responsibly, social media can also offer a variety of positive outcomes, such as the ability to stay connected with loved ones, network professionally, and access valuable information and resources.

One of the major benefits of social media is its ability to keep people connected. For example, individuals who live far apart can maintain close relationships through regular communication on these platforms. Social media also facilitates professional networking, allowing users to connect with potential employers or clients, and enabling companies to promote their products and services to a global audience. Additionally, platforms like Facebook, Twitter, and Instagram provide a space for people to share ideas, opinions, and creative work, fostering a sense of community and collaboration.

Despite these advantages, there are serious concerns about the negative impact of social media, particularly on mental health. Studies have shown that excessive social media use can contribute to feelings of anxiety, depression, and loneliness. This is often attributed to the unrealistic portrayals of life that are commonly shared on these platforms, leading to comparisons that can make individuals feel inadequate or left out. Furthermore, constant exposure to negative news or online bullying can exacerbate these feelings and contribute to long-term psychological stress.

Another issue with social media is its potential to distract people from their daily responsibilities. With notifications constantly popping up and endless streams of content to scroll through, individuals may find it difficult to focus on tasks such as work, school, or personal obligations. This can result in decreased productivity and a lack of attention to important matters.

Ultimately, the impact of social media depends on how it is used. If individuals are mindful of their usage patterns and take steps to limit their time on these platforms, they can enjoy the benefits of staying connected and informed without the negative consequences. Parents, educators, and mental health professionals can also play a role in helping young people develop healthy habits and manage their social media use effectively.

According to passage, which of the following is NOT a benefit of social media? 

Nội dung nào sau đây không phải là lịch sử của ngôi trường mà em đang học?

Hoạt động đối ngoại của Đảng Cộng sản Đông Dương trong giai đoạn 1930-1940 là

Đâu là ý đúng: Nhân tố nào sau đây ảnh hưởng đến khả năng tiếp cận điểm đến của khách du lịch?

Hình ảnh thường thấy trong thơ hai-cư là gì?

Chủ thể nào sau đây sẽ ban hành văn bản quy phạm pháp luật?

Read the following passage about Unconventional Teachers Who Changed Lives 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 23 to 30.

Traditional education focuses on textbooks, but some teachers go beyond these limitations. Mrs. Rodriguez transformed her classroom into a living laboratory. Her students conducted experiments with plants and simple machines. She believed hands-on learning creates deeper understanding than reading alone. When asked why she taught differently, she replied, "I want students to fall in love with discovery." Her methods helped struggling students improve and develop passion for science.

Mr. Jackson abandoned lectures for storytelling and role-playing. His students experienced history by acting out important moments. This approach made history come alive and helped them remember key information. One student said, "Before Mr. Jackson's class, I thought history was boring, but he showed us it's fascinating." He took classes to historical sites and invited veterans to share experiences. These connections helped students understand how past shapes our present.

In a remote village, Ms. Chen taught English without proper textbooks. She created materials using newspapers and song lyrics. Despite limited resources, her students achieved remarkable results through her dedication. "Learning should be joyful, not painful," she told questioning parents. Ms. Chen organized conversation clubs and pen pal exchanges. These activities gave students practical language skills and confidence to use English in real situations.

Coach Williams was a life mentor who taught valuable lessons through sports. He focused on teamwork and fair play rather than winning. Students who struggled academically often excelled in his class. "The playing field is where children learn who they truly are," he explained. He created inclusive activities for all students regardless of athletic ability. Many former students credit him with teaching life skills like resilience and cooperation that helped them succeed after graduation.

In which paragraph does the writer mention why Mrs. Rodriguez used hands-on experiments?

Vỏ Trái Đất ở đại dương có độ dày khoảng bao nhiêu?