Một mạch dao động điện từ có tần số 5 MHz, tốc độ ánh sáng trong chân không là 3.10⁸ m/s. Sóng điện từ do mạch đó phát ra có bước sóng là

Choose a suitable word or phrase (marked A, B, C, or D) to fill in each blank.

Bell experimented with ways of transmitting_____________ over a long distance.

Đâu không phải là ưu điểm của phương pháp khí canh so với phương pháp trồng cây trên đất?

Trong các mệnh đề bên dưới, mệnh đề nào đúng?

Thắng lợi của cuộc Cách mạng tháng Hai năm 1917 đã lật đổ được chính quyền nào sau đây? 

Mark the letter A, B, C or D on your answer sheet to indicate the best arrangement of utterances or sentences to make a meaningful exchange or text in each of the following questions from 13 to 17.

Dear Mark,

a. By the way, I’ve started taking a pottery class. It’s been so much fun getting my hands dirty and creating something from scratch. I remember you used to enjoy arts and crafts as well. Maybe you could join me for a class sometime!

b. I also took a weekend trip to the mountains last month. The views were breathtaking, and it was a nice escape from the city. We should plan a hiking trip together soon! I miss our adventures.

c. I hope this letter finds you well! It feels like ages since we last spoke. How have you been?

d. I wanted to share some exciting news with you! I recently got a promotion at work, and I’m now managing a small team. It’s a big step, but I’m really enjoying the challenges that come with it. Have you been working on any new projects lately?

e. Let me know how things are going on your end. I’d love to catch up over coffee or a video call soon.

Take care!

Best,

LK

Tập hợp nhiều tế bào cùng loại và cùng thực hiện một chức năng nhất định tạo thành yếu tố nào?

Which word or phrase is the best fits the numbered blank (13)

When he was a student, his father gave him a monthly ______ towards his expenses.

Ngân sách của nhà nước có vai trò như thế nào đối với sự phát triển của một quốc gia?

Mark the letter A, B, C or D on your answer sheet to indicate the best arrangement of utterances or sentences to make a meaningful exchange or text in each of the following questions from 13 to 17.

a. They bring people together, fostering a sense of belonging and unity among participants.

b. Festivals in Vietnam offer a vibrant celebration of culture and community.

c. These events showcase traditional music, dance, and cuisine, allowing attendees to experience the rich heritage of the country.

d. Overall, they create a joyful atmosphere that promotes cultural exchange and strengthens social bonds.

e. Festivals also boost local economies by attracting tourists, which helps small businesses thrive.

Trong không gian $Oxyz$, cho điểm $M_0(x_0;y_0;z_0)$ và mặt phẳng $(\alpha):Ax+By+Cz+D=0$. Khoảng cách từ điểm $M_0$ đến mặt phẳng $(\alpha)$ bằng

Căn cứ theo trạng thái kim loại mối hàn khi tiến hành nung nóng, công nghệ hàn chia thành mấy nhóm?

Một chiếc lều cắm trại được thiết kế có dạng hình chóp tứ giác đều với thể tích là \(6~{{\text{m}}^{3}}\). Bốn mặt bên của lều được may bằng vải bạt (hình minh họa). Để diện tích vải bạt cần dùng là nhỏ nhất, thì độ dài cạnh đáy gần nhất với giá trị nào sau đây?

Đối với ren thấy, đường đỉnh ren vẽ bằng nét gì?

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.

Why did the writer start the article with Borsi’s story in the first paragraph?

Mỗi phân tử glucose phân giải theo con đường lên men thu được bao nhiêu phân tử ATP?