Trong phản ứng tạo thành magnesium chloride từ đơn chất: Mg + Cl₂ → MgCl₂. Kết luận nào sau đây đúng?

Điền số nguyên dương thích hợp vào chỗ trống.

Cho hình hộp \(ABCD\cdot {A}'{B}'{C}'{D}'\) có \(A{A}'=a\). Gọi \(M,N\) là các điểm thuộc các cạnh \(B{B}'\) và \(D{D}'\) sao cho \(BM=\) \(DN=\frac{a}{3}\). Mặt phẳng \(\left( AMN \right)\) chia khối hộp thành hai phần, gọi \({{V}_{1}}\) là thể tích khối đa diện chứa \({A}'\) và \({{V}_{2}}\) là thể tích phần còn lại. Tỷ số \(\frac{{{V}_{1}}}{{{V}_{2}}}\) bẳng (……).

Phản ứng nào không thể hiện tính khử của glucozơ?

Một dây dẫn dài 50 cm được đặt vuông góc với một từ trường đều. Cường độ dòng điện trong dây là 10,0 A, lực do từ trường tác dụng lên dây là 3,0 N. Độ lớn cảm ứng từ của từ trường là

Từ năm 1884 đến năm 1945, thông qua nhiều hoạt động, chính quyền thuộc địa Pháp đại diện quyền lợi của Việt Nam trong quan hệ đối ngoại, luôn khẳng định chủ quyền của Việt Nam đối với quần đảo Hoàng Sa và quần đảo Trường Sa, ngoại trừ việc

Read the following passage about managing change 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. 

Growing up in Athens, Greece, Lydia Borsi remembers feeling tested when she tried to deal with mental health issues. Borsi says she had been seeing a therapist for anxiety. But she notes that people in Greece do not openly discuss mental health issues, which also get little attention in general healthcare services. “It was a lot more secretive. And people thought that I was a lot more unique,” Borsi said.

That all changed in 2017 when she moved to the United States to study at the University of Rochester in Rochester, New York. “When I came here, I really liked that people were not afraid to speak up about mental health and say that it’s important,” she said. The university was very supportive of her needs and offered plenty of information. She also became involved with a school group called Active Minds that helps students deal with mental health issues. [A]

Then due to the spread of the novel coronavirus, the University of Rochester had to move all its classes and some of its mental health resources online. Luckily, Borsi was able to connect with a mental health expert outside the school, in the local community. [B]

But as many of her American friends returned home, Borsi was stuck. Greece had succeeded in limiting the spread of the virus within its borders, but flights there from the U.S. are barred until July. Also, the health crisis has put her plans to seek admission to medical school in Britain on hold. [C] And she is not alone.

[D] In April, Active Minds launched a survey of over 2,000 students at U.S. colleges and universities. The study found that over 80 percent of those asked said the coronavirus crisis had negatively affected their mental health. One in five said it has affected them severely.

Laura Horne, chief program officer at Active Minds, says the findings are especially troubling given that the crisis is only going to make it harder for colleges and universities to help these students. “Colleges and universities had to pivot rather quickly to respond to COVID-19 and figure out all facets of university life, including mental health services. Now they have to figure out how to communicate with students,” Horne said.

Frank Chen is a Houston, Texas-based psychiatrist who has worked with college-age young adults. He points out that individuals at that age are in an important stage of their mental development. And college can be a difficult experience for students with or without mental health issues, as they balance work, studies, and personal relationships. Adding a major world event, like the spread of the coronavirus, makes it very difficult to predict what the long-term psychological effects might be. “I don’t think that there’s another event in the history of the people who are alive now that can really measure up to this,” said Chen.

Which of the following would be the best title for this article?

Muốn lò xo có độ cứng k = 100 N/m dãn ra một đoạn 5 cm ta phải treo vào lò xo một vật có khối lượng bằng bao nhiêu ? Lấy g = 10 m/s².

Read a flyer promoting a new gym. Decide if the statements are true (T) or false (F). 

About us

You don't want just a gym membership. You want a membership that means something. And that means you need support, expert help and a community.

Best Body Fitness isn't just a gym: it's a full-service fitness membership made for you.

Here's how it works:

STEP ONE: Your assessment

We begin with an assessment session. This is a chance for you to see what we do at Best Body. Our assessment plans are no-cost and no-risk. We'll also make a training plan specifically for you.

STEP TWO: Your training

When you decide to become a Best Body member, we show you what to do, how to do it and why you are doing it. After a few sessions with an expert private trainer you will feel comfortable working out on your own. But don't worry, we'll always be nearby if you have questions.

STEP THREE: Your membership

Membership works on a month-to-month basis. There are no sign-up fees and no cancellation fees. Start and stop whenever you want. And the best part? Our fees are the most competitive in the whole downtown area.

STEP FOUR: Your community

At Best Body Fitness, we see everyone as part of a big team. And when you work with a team, you can do great things. Join any of our specialized classes, led by expert instructors. Come to our nutrition classes. Participate in our regular social events. Everything is included in your fee.

At this gym, you always do exercise with an expert instructor.

Theo em, vì sao chúng ta cần tiêu dùng hợp lí và có kế hoạch?

Ý nào sau đâyđúng khi nói về cạnh tranh trong nền kinh tế thị trường?

Trong thí nghiệm nhận biết lipid bằng phép thử nhũ tương, nếu sử dụng dầu ăn để thử thì huyền phù tạo ra sẽ có màu

Choose the best answer to fill in the blank (12)

Read the following passage about Preserving Today's Soundscapes for Future Generations 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.

Sonic time capsules save today's sounds for future people. Scientists capture everyday sounds like streets, birds, and children playing in parks around the world. These recordings help us remember our world before changes. Cities are losing unique sounds as life becomes similar everywhere. Old machines, music, and natural sounds might disappear if not saved. Many important cultural sounds are already lost forever because nobody thought to record them when they still existed.

Sound collectors use microphones to record in different places. They visit forests, oceans, cities, and villages to capture soundscapes throughout different seasons and times of day. They store sounds in digital libraries for years. Museums have rooms for listening to past sounds. These experiences help people understand history in ways books cannot. Some researchers travel to remote locations to record indigenous languages and traditional ceremonies before they vanish from our collective memory.

Climate change is changing world sounds. Melting glaciers, endangered animals, and disappearing languages need saving before they're gone. Researchers believe future people will want to know how our world sounded. These capsules will be important records, like photographs. Scientists study how sounds affect human health. The sounds of nature can reduce stress and improve mental health, which makes preserving natural soundscapes even more important for future generations who may live in highly urbanized environments.

Community projects invite people to record daily sounds. Children learn to listen carefully to the world around them and identify sounds that matter to their community. Old people share recordings from their childhood. People feel emotions when listening to these collections. Artists create music using everyday recordings. These projects help communities protect special sounds for the future. Some cities now have sound preservation policies that protect unique acoustic environments just as they would protect historic buildings or natural landscapes from development.

In which paragraph does the writer mention why researchers are collecting sounds affected by climate change?

Mark the letter A, B, C, or D on your answer sheet to indicate the sentence that is closest in meaning to each of the following questions.

John said, “You’d better not lend them any money, Daisy.”

Cho hàm số \(y=f(x)\) có đạo hàm \(\forall x \in \mathbb{R}\), hàm số \(f^{\prime}(x)=x^{3}+a x^{2}+b x+c\) có đồ thị như hình vẽ.

Ý nào sau đây là thể hiện khái niệm của ngân sách nhà nước?

Ảnh hưởng nào của liên kết hydrogen đến tính chất của các chất không đúng?

Một phòng trưng bày trong bảo tàng nghệ thuật sử dụng bộ gồm bốn đèn cảm biến được lắp đặt tại các vị trí \(A(1 ; 3 ; 4), B(3 ; 4 ; 5), C(2 ; 2 ; 2)\) và \(D(4 ; 3 ; d)\). Biết rằng bộ đèn chỉ hoạt động tốt nếu cả bốn đèn cùng nằm trên một mặt phẳng. Muốn bộ đèn hoạt động tốt thì cần điều chỉnh lắp đặt sao cho \(d\) bằng bao nhiêu? (Kết quả viết dưới dạng số thập phân)

Nguyên tử aluminium (Al) có 13 proton và 14 neutron. Kí hiệu nguyên tử của nguyên tố này là