Cho tập hợp $A = \{2 ; 4 ; 6 ; 9\}$; $B = \{1; 2 ; 3 ; 4\}$. Tập hợp $A \backslash B$ bằng tập hợp nào sau đây?

Read the following passage about Wildlife Conservation in Africa 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.

Wildlife conservation in Africa is vital for preserving biodiversity and ensuring the survival of iconic species such as elephants, lions, and rhinos. [I] The continent is home to some of the world’s most diverse ecosystems, including savannahs, rainforests, and deserts. [II] Conservation efforts involve strategies like protecting habitats, combating poaching, and raising awareness about the importance of wildlife. [III] Despite challenges, success stories demonstrate the positive impact of these efforts. [IV]

One notable example comes from Kenya, where anti-poaching initiatives and community engagement have helped stabilize elephant populations in Amboseli National Park. Similarly, in South Africa, rhino conservation programs use advanced technologies like drones and GPS tracking to monitor and protect vulnerable animals. These efforts not only safeguard wildlife but also promote eco-tourism, which supports local economies.

However, wildlife conservation in Africa faces persistent threats. Habitat loss due to agricultural expansion and urbanization continues to endanger species. Climate change exacerbates these challenges, altering migration patterns and threatening ecosystems. Furthermore, poaching and the illegal wildlife trade remain significant concerns, driven by global demand for products such as ivory and rhino horn.

To overcome these challenges, conservationists emphasize the need for international collaboration and local community involvement. Initiatives like eco-tourism provide financial incentives for communities to protect wildlife. Governments, NGOs, and individuals must work together to ensure the survival of Africa’s unique species for future generations.

The phrase “combating poaching” in paragraph 1 could best be replaced by?

Chọn phát biểu đúng về electron s?

Công suất tiêu thụ năng lượng điện của đoạn mạch được tính bằng?

Read the following passage about urban shift and mark the letter A, B, C, D on your answer sheet to indicate the best answer to each of the following questions from 31 to 40.

[I] Sperm whales are fascinating creatures. [II] They possess the biggest brain of any species, six times larger than a human’s, which scientists believe may have evolved to support intelligent, rational behavior. [III] They’re also highly social and capable of making decisions as a group. [IV] But there’s also a lot we don’t know about them, including what they may be saying to one another when communicating with a system of short clicks, known as codas.

Now, new research published in Nature Communications today suggests that sperm whales’ communication is actually much more expressive and complicated than was previously thought. A team of researchers led by Pratyusha Sharma at MIT’s Computer Science and Artificial Intelligence Lab (CSAIL) working with Project CETI, a nonprofit focused on using AI to understand whales, used statistical models to analyze whale codas and managed to identify a structure to their language that’s similar to features of human language. Their findings represent a tool future researchers could use to decipher not just the structure but the actual meaning of whale sounds.

For the study, the researchers examined recordings of 8,719 codas from around 60 whales collected by the Dominica Sperm Whale Project between 2005 and 2018, using a mix of AI algorithms for pattern recognition and classification. The AI then turned the clicks within the coda data into a new kind of data visualization called an exchange plot, revealing that some codas featured extra clicks. These extra clicks, combined with variations in the duration of their calls, appeared in interactions between multiple whales, which they say suggests that codas can carry more information and possess a more complicated internal structure than we had previously believed.

The team’s next step is to build language models of whale calls and to examine how those calls relate to different behaviors. They also plan to work on a more universal system that could be used across species, says Sharma. Taking a communication system we know nothing about, working out how it encodes and transmits information, and slowly beginning to understand what’s being communicated could have many purposes beyond whales. “I think we’re just starting to understand some of these things,” she says. “We’re very much at the beginning, but we are slowly making our way through.”

What do we learn about sperm whales in paragraph 1?

Để nhập từ bàn phím biến b kiểu thực ta viết:

Lợi thế nổi bật nhất để Đông Nam Bộ hình thành các vùng chuyên canh cây công nghiệp quy mô lớn là

Chọn từ/ cụm từ thích hợp nhất để điền vào chỗ trống trong các câu dưới đây.

Cơ cấu dân số nước ta có sự chuyển biến theo hướng: ______ nhóm tuổi 0 – 14 tuổi giảm trong khi nhóm tuổi 15 – 59 và nhóm trên 60 tuổi ______ .

Tọa độ giao điểm của \(\left( P \right)\,:\,y = {x^2} - 4x\) với đường thẳng \(d\,:\,y = - x - 2\) là?

Cho hai tập hợp $A=\left(1;5 \right]; \, B=\left(2;7 \right]$. Tập hợp $A\backslash B$ là

Trong không gian với hệ tọa độ Oxyz, cho ba vectơ \(\vec{a}=\left( 5;7;2 \right),\vec{b}=\left( 3;0;1 \right),\vec{c}=\left( -6;1;-1 \right)\). Tọa độ của vectơ \(\vec{m}=3\vec{a}-2\vec{b}+\vec{c}\) là

Which of the following best restates each of the given sentence?

The boy was not intelligent enough to have solved such complex problems alone.

Trong nền kinh tế của nước ta, đâu là hoạt động cơ bản nhất đóng vai trò quyết định các hoạt động còn lại?

Nguyên tử X có tổng số hạt cơ bản là 77, trong đó số hạt mang điện nhiều hơn số hạt không mang điện là 19. Cho các phát biểu sau:

(a)   Nguyên tử X có số khối là 53

(b)   Nguyên tử X có 7electron s

(c)   Lớp M của nguyên tử X có 13 electron

(d)   X là nguyên tố s

(e)   X là nguyên tố kim loại

(f)    X có 4 lớp electron

Trong các phát biểu trên, số phát biểu đúng là

Đặc điểm nào không đúng với nền kinh tế Liên bang Nga?

Choose A, B, C or D that has the CLOSEST meaning to the underlined word/phrase in each question.

People believe that cities of the future will increase the general well-being of individuals and societies.

Trồng rau cải ngọt áp dụng cho loại mô hình nào sau đây?

Mĩ giữ thái độ “trung lập” trong giai đoạn đầu của cuộc chiến tranh thế giới thứ nhất vì:

Phát biểu bằng lời của mệnh đề $P$: ''$\exists x \in \mathbb{Z}, \, x^2=1$'' là

Ngân sách Nhà nước cần được cơ quan nào thông qua trước khi thi hành?

Nếu \(C_{n}^{1}+6C_{n}^{2}+6C_{n}^{3}=9{{n}^{2}}-14n\) thì n bằng: