Tại một điểm trên mặt chất lỏng có một nguồn dao động với tần số 120 Hz, tạo ra sóng ổn định trên mặt chất lỏng. Xét 5 gợn lồi liên tiếp trên một phương truyền sóng, ở về một phía so với nguồn, gợn thứ nhất cách gợn thứ năm 0,5 m. Tốc độ truyền sóng trên mặt chất lỏng là
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Glycerol có công thức là \({{\text{C}}_{3}}{{\text{H}}_{5}}{{(\text{OH})}_{3}}\), được sử dụng để kiểm soát độ ẩm và giúp tăng cường độ kết dính trong kem dưỡng da. Nhận định đúng về glycerol là:
Cho hàm số
. a)
. b)
liên tục trên 
. c)
. d)
. Read the following passage about How Failures Led to Breakthroughs 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.
Many important discoveries happened because of mistakes and unexpected accidents. Alexander Fleming found penicillin when he left his laboratory messy before going on holiday. After vacation, he saw mold growing on his experiment plate. Fleming noticed this mold killed bacteria around it very effectively. This fortunate accident later saved millions of lives around the world. Scientists call finding valuable things by chance "serendipity," which happens often in research.
The Post-it Note began as a mistake that seemed useless at first. In 1968, Spencer Silver tried making a strong glue for 3M company but created a weak one instead that didn't stick permanently. Nobody knew what to do with this disappointing result for several years. Then his colleague Arthur Fry realized this "failure" could make perfect bookmarks that wouldn't damage pages when removed. This weak adhesive eventually became one of the most popular office products worldwide, changing how people work.
In cooking, many favorite foods came from kitchen errors and quick substitutions. Ruth Wakefield invented chocolate chip cookies when she ran out of baker's chocolate and used broken pieces of semi-sweet chocolate instead. She thought they would melt completely in the dough, but they kept their shape during baking. Potato chips were created when chef George Crum made extremely thin potatoes to annoy a customer who repeatedly complained about thick fries. Surprisingly, the customer loved them and ordered more!
These fascinating stories teach us that mistakes can lead to new opportunities and unexpected innovations. Thomas Edison said about his many failed light bulb attempts, "I haven't failed. I've just found 10,000 ways that don't work." This positive attitude shows we should see errors as valuable learning chances. Smart people don't fear making mistakes in their work; they fear missing opportunities to learn from them and discover something amazing.
The word “their” in paragraph 3 refers to _________.
Circle A. B. C or D to indicate the correct answer to each of the following questions
Who suggested_______here for the picnic?
Đổ 1,5 lít nước ở 200C vào một ấm nhôm có khối lượng 600g và sau đó đun bằng bếp điện. Sau 35 phút thì đã có 20% khối lượng nước đã hóa hơi ở nhiệt độ sôi 1000C. Biết rằng 75% nhiệt lượng mà bếp cung cấp được dùng vào việc đun nước. Cho biết nhiệt dung riêng của nước là 4190J/kg.K, của nhôm là 880J/kgK nhiệt hóa hơi của nước ở 1000C là 2,26.106J/kg, khối lượng riêng của nước là 1kg/l. Tính công suất cung cấp nhiệt của bếp điện là bao nhiêu?
Read the following advertisement about a new travel platform 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.
UNDERSTANDING GLOBALIZATION
Have you ever wondered how various countries become more interconnected? Globalization is the process (1) _____ for the exchange of ideas, goods, and services across the world. This phenomenon has (2) _____ many businesses to expand their markets beyond national borders. With the rise of technology and communication, companies can now communicate (3) _____ customers and partners globally. However, globalization also raises important questions about cultural identity and economic inequality. (4) _____ losing our local traditions in favour of a more homogenized culture? To explore these issues, join our upcoming seminar on globalization. Experts will discuss (5) _____ economies and societies. They will also provide insights into how we can navigate this complex landscape. Don't miss this opportunity (6) _____ your understanding of the world!
- Trong quá trình trồng trọt, người nông dân được khuyến cáo không bón vôi sống (thành phần chính là CaO) cùng với phân đạm ammonium. Nguyên nhân của khuyến cáo này là
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.
HASTAG ACTIVISM - WORTH CLICKING ON?
Platforms like Facebook and Twitter are being used more and more to ___(1)___ awareness of social issues and ___(2)___ for good causes. There have been several examples of ___(3)___ campaigns in recent years. For instance, the #IceBucketChallenge proved a viral success in raising awareness and funds ___(4)___ ALS, a disease that ___(5)___. Not only did people all over the world post videos of themselves tipping a bucket of iced water over their heads, ___(6)___ they also nominated other people to do the challenge, as well as donating to the Association.
(Adapted from Friends Global)
Một lượng khí lý tưởng có thể tích ban đầu là \({{V}_{1}}\), áp suất là \({{P}_{1}}\), và nhiệt độ tuyệt đối là \({{T}_{1}}\). Nếu thể tích tăng gấp đôi và nhiệt độ tuyệt đối tăng gấp ba lần, thì áp suất mới \({{P}_{2}}\) của khí sẽ
Người ta thường dùng quãng đường đi được trong cùng một đơn vị thời gian để xác định độ nhanh, chậm của chuyển động. Đại lượng này gọi là
Kí hiệu phân lớp nào sau đây là sai?
Mark the letter A, B, C, or D on your answer sheet to indicate the sentence that best combines each pair of sentences in the following questions.
Safety instructions are given in symbols. People can quickly comprehend them.
Read the following passage about cultural diversity and mark the letter A, B, C, or D to indicate the option that best fits each of the following questions from 31 to 40.
[I] Belgium features a fascinating mix of ancient traditions and contemporary legislation, showcasing the country’s rich history. [II] In Belgium, the families of the bride and groom each pitch in by providing a sheet of paper for the wedding invitations, in line with a long-standing tradition. [III] The wedding invitations symbolize the new partnership and the merging of the two families. [IV]
In an old Belgian tradition meant to bring the two families closer together, the bride would pause halfway down the aisle to give her mother a solitary flower. They hold each other’s arms. The newlyweds then make their way to the groom’s mother-in-law during the recessional, where the bride presents her with a solitary flower as a token of her affection. As a sign of the bride’s acceptance of her new mother, they embrace.
Carrying a uniquely embroidered handkerchief bearing the bride’s name is one of the most significant and long-standing customs of the Belgian wedding. This handkerchief will be framed and displayed in a special spot after the wedding. Before each subsequent female member of the bride’s family is married, the handkerchief is taken out of its frame, embroidered with the name of the new bride, and then passed down through the generations. A bridal handkerchief is a treasured memento that is passed down through the generations.
There are two big chairs placed near the altar where the bride and groom sit during the wedding mass, representing their throne as king and queen for the day and the location. As the ceremony comes to a close, the groom places the wedding ring on the third finger of the bride’s left hand. Because it is a circle, the ring represents love that knows no bounds, and the third finger of the left hand represents love because it is thought to hold the vein that goes to the heart. Soon after the wedding, the newlyweds kiss for the first time as husband and wife. Because each partner takes a breath of their new spouse’s spirit, the kiss is a metaphor for the couple’s spiritual union.
Traditionally, as the bride and husband leave the church, the bridesmaids gather a handful of pennies and then scatter them among the less fortunate outside. The happy couple might increase their chances of financial success by donating to charity.
A honeymoon is for the newlyweds after the wedding. Honey wine, or mead, was traditionally drunk during the 28-day honeymoon, which corresponds to one lunar cycle, in ancient times. The purpose of this was to prevent the bride’s relatives from attempting to reclaim their daughter from her husband.
Which of the following best paraphrases the underlined sentence in paragraph 6?
Mark the letter A, B, C, or D on your answer sheet to indicate the correct option that best fits each of the numbered blanks from 18 to 23.
Music brings many benefits to our lives, especially when we learn something new. Firstly, it makes learning more enjoyable. When we listen to music while studying, it can help us feel relaxed and happy. (18) _______. For example, if you are learning a new language, listening to songs in that language can help you understand and remember words better.
Secondly, music helps us focus. (19) _______, our mind becomes less distracted. We can concentrate better on our tasks, whether it’s reading, writing, or solving problems. This is because music has a special way of grabbing our attention and (20) _______.
Finally, music connects us with other cultures. Through music, we can learn about the traditions, feelings, and (21) _______. It’s like traveling to new places without leaving (22) _______. We can hear different instruments, rhythms, and voices that tell us about the rich diversity of our world.
In summary, music is not just about entertainment. It helps us learn better, stay focused, and (23) _______. It’s a powerful tool that can make our learning journey more exciting and rewarding.
Hình thức dinh dưỡng chủ yếu của vi khuẩn lam là gì?
Đâu là ý đúng: Phương pháp thứ hai để điều khiển tốc độ động cơ một pha là?
Nước ta có bao nhiêu chủ thể chính tham gia trong nền kinh tế?
Read the following passage about the Pathways from Today's Actions to Tomorrow's World 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.
As we stand at the crossroads of environmental decision-making, the actions we take today will shape our world in 2050. Scientists warn that we're skating on thin ice with current consumption patterns and carbon emissions. Global temperatures could rise by 2-4 degrees Celsius unless significant changes occur within the next decade. Many countries have pledged to achieve carbon neutrality by 2050, but these promises require immediate implementation. Individual choices in transportation, energy usage, and consumption can collectively influence whether future generations inherit a sustainable planet or face severe climate consequences.
[I] Technological innovation represents our greatest hope for addressing environmental challenges by 2050. [II] Renewable energy sources like solar and wind are becoming increasingly affordable, potentially replacing fossil fuels entirely within thirty years. [III] Electric vehicles may dominate transportation networks, while vertical farming could transform food production in urban areas. [IV] However, these technological solutions must be developed and deployed equitably to avoid creating new disparities between wealthy and developing nations.
Social structures will undergo dramatic transformation by 2050 as demographic shifts reshape communities worldwide. Aging populations in developed countries will necessitate new approaches to healthcare, retirement, and social support systems. Meanwhile, climate migration may force millions to relocate from vulnerable coastal and drought-prone regions. Education systems must evolve to prepare our students for jobs that don't yet exist, emphasizing their adaptability and lifelong learning. Cities will need to become more resilient, incorporating green spaces and sustainable infrastructure to support growing populations.
Economic models must fundamentally change by 2050 to balance prosperity with environmental responsibility. The traditional focus on continuous growth may shift toward measuring success through wellbeing indicators rather than GDP alone. Circular economy principles will likely replace linear production models, with products designed for reuse and recycling. Resource-sharing platforms may become more prevalent, reducing individual consumption while maintaining living standards. Companies implementing genuinely sustainable practices will thrive, while those clinging to environmentally harmful methods may disappear entirely. The transition presents both challenges and opportunities for businesses willing to embrace innovation and sustainability.
Which of the following is TRUE according to the passage?
Nguồn lao động nước ta dồi dào là điều kiện thuận lợi để
