Khẳng định đúng là:
A. Nguyên tử có cấu tạo đặc khít, gồm hạt nhân ở trung tâm và lớp vỏ là các electron chuyển động xung quanh hạt nhân.
B. Nguyên tử có cấu tạo rỗng, gồm hạt nhân ở trung tâm và lớp vỏ là các electron chuyển động xung quanh hạt nhân.
C. Nguyên tử có cấu tạo rỗng, gồm electron ở trung tâm và hạt nhân chuyển động xung quanh.
D. Nguyên tử có cấu tạo đặc khít, gồm electron ở trung tâm và hạt nhân chuyển động xung quanh.
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Câu hỏi liên quan
Ở điều kiện thường, iodine là chất rắn dạng tinh thể màu đen tím. Khi đun nóng, sẽ diễn ra quá trình thăng hoa. Sự thăng hóa đó là sự chuyển từ:
Read the following advertisement and mark the letter A, B, C, or D on your answer sheet to indicate the option that best fits each of the numbered blanks from 1 to 6.
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Hình dưới đây mô tả đồ thị độ dịch chuyển - thời gian của một chiếc xe ô tô chạy trên một đường thẳng. Vận tốc trung bình của xe là
The doctors are operating on the boy __________ fingers were lost because of firecrackers.
Pininfarina Battista 2020 đang là siêu xe tăng tốc nhanh nhất thế giới khi chỉ mất 1,9s để đạt vận tốc 100 km/h có khối lượng khoảng 1996 kg. Lực để tạo ra gia tốc này là bao nhiêu?
chọn đúng hoặc sai với mỗi ý a), b), c), d)
Hình bên biểu diễn sự thay đổi độ phóng xạ của một mẫu chất phóng xạ \({\beta ^ - }\)theo thời gian.
Trong các câu sau, có bao nhiêu câu là mệnh đề?
(i) Hãy mở cửa ra!
(ii) Số 25 chia hết cho 8.
(iii) Số 17 là số nguyên tố.
(iv) Bạn thích ăn phở không?
Số tập con có 2 phần tử của tập M = {1; 2; 3; 4; 5; 6}
Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer.
Global Issues: Gender Equality and Women’s Empowerment
Gender equality means that men and women have equal power and equal opportunities for financial independence, education, and personal development. Women's empowerment is a critical aspect of achieving gender equality. It includes increasing a woman's sense of self-worth, her decision-making power, her access to opportunities and resources, her power and control over her own life inside and outside the home, and her ability to effect change. Yet gender issues are not focused on women alone, but on the relationship between men and women in society. The actions and attitudes of men and boys play an essential role in achieving gender equality.
Education is a key area of focus. Although the world is making progress in achieving gender parity in education, girls still make up a higher percentage of out-of-school children than boys. Approximately one quarter of girls in the developing world do not attend school. Typically, families with limited means who cannot afford costs such as school fees, uniforms, and supplies for all of their children will prioritize education for their sons. Families may also rely on girls' labor for household chores, carrying water, and childcare, leaving limited time for schooling. But prioritizing girls' education provides perhaps the single highest return on investment in the developing world. An educated girl is more likely to postpone marriage, raise a smaller family, have healthier children, and send her own children to school. She has more opportunities to earn an income and to participate in political processes, and she is less likely to become infected with HIV.
Women's health and safety is another important area. HIV/AIDS is becoming an increasingly impactful issue for women. This can be related to women having fewer opportunities for health education, unequal power in sexual partnership, or as a result of gender-based violence. Maternal health is also an issue of specific concern. In many countries, women have limited access to prenatal and infant care, and are more likely to experience complications during pregnancy and childbirth. This is a critical concern in countries where girls marry and have children before they are ready; often well before the age of 18. Quality maternal health care can provide an important entry point for information and services that empower mothers as informed decision-makers concerning their own health and the health of their children.
A final area of focus in attaining gender equality is women's economic and political empowerment. Though women comprise more than 50% of the world's population, they only own 1% of the world's wealth. Throughout the world, women and girls perform long hours of unpaid domestic work. In some places, women still lack rights to own land or to inherit property, obtain access to credit, earn income, or to move up in their workplace, free from job discrimination. At all levels, including at home and in the public arena, women are widely underrepresented as decision-makers. In legislatures around the world, women are outnumbered 4 to 1, yet women's political participation is crucial for achieving gender equality and genuine democracy.
What is the tone of the author in the passage?
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 from 29 to 33.
International Women’s Day, celebrated on March 8th, is a time to honor women’s progress and advocate for real change towards gender equality. This day, rooted in a 1908 demonstration where 15,000 women in New York City stood united for equal rights, better pay, shorter hours, and voting rights, has grown into a worldwide movement. Clara Zetkin, at a meeting in 1910, suggested a special day each year to focus on women’s rights, leading to the first International Women’s Day in 1911.
Despite some beliefs that women have equal chances as men, the reality often tells a different story. Girls worldwide face more household duties than boys and are more likely to miss out on school. In many countries, equal education for both genders is not guaranteed, and many girls are married off young, which can force them to end school early, lead to early pregnancy together with other health issues, and increase the chance of domestic violence.
On International Women’s Day, people participate in activities that raise awareness and call for gender equality. Wearing purple, a color of women’s rights history, is common. It is also a day when women are celebrated with gifts and social recognition in some places.
The journey towards full gender equality continues to face challenges. Yet, women’s groups across the globe remain strong and active, with younger women and teenagers adding their voices and energy to the cause. They are organizing, speaking out, and urging a shift in how we view and act towards each other regarding gender roles.
(Adapted from https://learnenglishteens.britishcouncil.org/)
What does the word “It” in paragraph 3 refer to?
Cho đồ thị độ dịch chuyển - thời gian như hình dưới. Đặc điểm của đồ thị này.
Choose the word or phrase among A, B, C or D that best fits the blank space following passage So you’re between the ages of thirteen and eighteen. What (36) _______ you happy? There have been lots of surveys about teenagers and happiness and they all come to different conclusions. Some surveys say that most young people are happiest (37) _________ they spend time with their family. Others say it’s when they’re (38) ________ friends. Some teenagers think that getting good marks at school and (39) _________ exams makes them happy and others feel that it’s having a boyfriend or girlfriend that improves their lives. The problem is that there isn’t just one thing that makes everyone happy. (40) __________ is something different for each of us, and what made us happy last week might not make us happy next week!
(37) _______
Một nguyên tố R có Z = 16. Có bao nhiêu phát biểu đúng về R trong các phát biểu sau:
(1) Công thức oxit cao nhất có dạng RO3
(2)Nguyên tử R có 4 electron ở lớp ngoài cùng
(3) R là nguyên tố họ p
(4) R là kim loai
Cho phản ứng tạo thành propene từ propyne:
\(C{{H}_{3}}-\text{C}\equiv CH\left( \text{g} \right)+{{\text{H}}_{2}}\left( \text{g} \right)\xrightarrow{{{\text{t}}^{0}},Pd/PbC{{O}_{3}}}C{{H}_{3}}-CH=C{{H}_{2}}\left( \text{g} \right)\)
Cho giá trị trung bình của các năng lượng liên kết ở điều kiện chuẩn:
Liên kết
C – H
C – C
C = C
C ≡ C
H - H
Eb (kJ/mol)
413
347
614
839
432
Biến thiên enthalpy chuẩn của phản ứng là
Nội dung nào sau đây không đúng khi nói về hình thức hoạt động của Quốc hội?
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
[I] A newborn baby can see, hear and feel. By the age of five, a child can talk, ride a bike and invent imaginary friends. How does this development happen? [II]We don't understand the way language, thinking and planning develop very well. [III]Now scientists are using new technology to ‘see’ into children's brains. And they are discovering new information about the way a baby's brain develops. [IV]
A study in 2010 showed that children who were afforded more focus often gained an edge in IQ. The brain of a newborn infant contains nearly a hundred billion neurons. This number is comparable to that of an adult's brain. As they mature, an infant assimilates information through the sensory modalities of sight, hearing, smell, taste, and touch. This information fosters intricate connections between different regions of the brain. By the age of three, there are approximately a hundred trillion synaptic connections.
One experiment looked at images of babies' brains while they were listening to different sounds. The sounds were in different sequences. For example, one sequence was mu-ba-ba. This is the pattern ‘A-B-B’. Another sequence was mu-ba-ge. This is the pattern ‘A-B-C’. The images showed that the part of the brain responsible for speech was more active during ‘A-B-B’ patterns. This shows that babies can tell the difference between different patterns. This experiment is interesting because sequences of words are important to grammar and meaning. Compare two sentences with the same words in a different order: ‘John killed the bear’ is very different from ‘The bear killed John.’ So babies are starting to learn grammatical rules from the beginning of life.
Researchers also know that babies need to hear a lot of language in order to understand grammar rules. But there is a big difference between listening to television, audiobooks or the internet, and interacting with people. One study compared two groups of nine-month-old American babies. One group watched videos of Mandarin Chinese sounds. In the other group, people spoke the same sounds to the babies. The test results showed that the second group could recognize different sounds, however, the first group learned nothing. The scientist, Patricia Kuhl, said this result was very surprising. It suggests that social experience is essential to successful brain development in babies.
The word “This” in paragraph 3 refers to:
Bản kế hoạch về thu chi ngân sách nhằm thực hiện một mục tiêu tài chính trong một thời gian ngắn (dưới 3 tháng) gọi là kế hoạch tài chính cá nhân gì?
Tin học đóng vai trò quan trọng trong sự phát triển của xã hội hiện đại, ảnh hưởng đến hầu hết các lĩnh vực từ giáo dục, y tế đến kinh doanh và chính phủ. Công nghệ thông tin giúp tối ưu hóa quy trình làm việc, nâng cao hiệu suất và tiết kiệm thời gian. Nhờ có Internet và các ứng dụng số, con người dễ dàng truy cập thông tin, giao tiếp và hợp tác trên toàn cầu. Bên cạnh đó, tin học còn góp phần vào việc phát triển các giải pháp thông minh cho các vấn đề xã hội, từ quản lý tài nguyên đến bảo vệ môi trường. Cuối cùng, tin học cũng thúc đẩy việc hình thành các kỹ năng mới, đáp ứng nhu cầu của thị trường lao động trong kỷ nguyên số.
Dưới đây là một số ý kiến về thông tin trên:
Cho các chất sau: CH3NH2, CH3NHCH3, (CH3)3N, CH3CH2NH2. Số chất thuộc loại amin bậc I?
Read the passage carefully.
1. It is estimated that about 40 per cent of the world's population use social media, and many of these billions of social media users look up to influencers to help them decide what to buy and what trends to follow. An influencer is a person who can influence the decisions of his or her followers because of his or her knowledge or special knowledge in a particular area, e.g. fashion, travel, or technology. Influencers are now seen by many companies as a direct way to customers' hearts. Brands are now asking powerful influencers to market their products. With some influencers charging up to $25,000 for one social media post, it is no surprise that more and more people are keen to become influencers, too. If you are one of them, then here are five tips on how to do it.
2. Choose your niche: What is the area that you know most about? What do you feel most excited talking about? Find the specific area that you are most interested in and develop it.
3. Choose your medium and write an interesting bio: Most influencers these days are bloggers and micro-bloggers. Decide which medium – such as your own online blog, Instagram or Snapchat – is the best way to connect with your followers and chat about your niche area. When you have done that, write an attention-grabbing bio that describes you and your speciality area in an interesting and unique way. Make sure that people who read your bio will want to follow you.
4. Post regularly and consistently: Many influencers post daily on their social media accounts. The more you post, the more likely people will follow you. Also, make sure that your posts are consistent and possibly follow a theme.
5. Tell an interesting story: Whether it is a photo or a comment that you are posting, use it to tell a story that will catch the attention of your followers and help them connectwith you.
6. Make sure people can easily find your content: Publicize your posts on a variety of social media by hashtags and catchy titles to make sure that they can be easily found. There is no point writing the most exciting blogposts or posting the most attractive photographs if no one is going to see them.
7. Most importantly, if you want to become a social media influencer, you need to have patience. Keep posting and your following will gradually increase. Good luck!
Choose an option (A, B, C, or D) that best answers each question.
In paragraph 2, what is the word niche closest in meaning to?