Zinc là một kim loại thường được tách chiết từ quặng của nó bằng nhiều phương pháp khác nhau. Một trong những phương pháp chính thường được sử dụng là nung nóng quặng ZnS trong lò rồi hòa tan sản phẩm ZnO trong sulfuric acid thu được dung dịch ZnSO₄, tinh chế dung dịch này rồi tiến hành điện phân thu được Zn. Để thu được duy nhất kim loại Zn và không có sản phẩm khác thì trong dung địch điện phân không có chứa ion nào sau đây?

Nội dung nào sau đây thể hiện ý nghĩa của các nội dung về phát triển khoa học, công nghệ và môi trường được quy định tại Hiến pháp?

Sử dụng các kí hiệu đoạn, khoảng, nửa khoảng để viết tập hợp $A = \{ x \in \mathbb{R} \Big| 7 \le x \le 10\}$.

Hàm số \(y=3 \cos \left(\frac{\pi}{4}-m x\right)\) tuần hoàn có chu kì \(T=3 \pi\) khi

Dựa trên cơ sở nào sau đây để phân chia các quốc gia trên thế giới thành nhóm nước phát triển và đang phát triển?

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 from 31 to 40.

Mountain Lions Amid Wildfires: A Struggle for Survival

Beth Pratt, the California director for the National Wildlife Federation, has spent her career protecting Los Angeles’ mountain lions. These top predators live in a rocky area surrounded by fancy houses and many roads. When wildfires destroy vast stretches of open land, the survival options for these animals become critically limited. “This is the LA area—these mountain lions can’t just move into the Kardashians’ backyard,” Pratt says, her voice filled with concern for the animals in such a difficult situation.

(I) The chaparral vegetation, covering about 10% of California, is one of the world’s most flammable ecosystems. (II) In Los Angeles, suburban sprawl intrudes on these areas, blocking wildlife escape routes. (III)Fires strip the land of food and shelter, transforming vibrant ecosystems into barren landscapes. (IV) Pratt highlights the urgency of the situation, explaining how areas that once supported life are now “taken out of commission,” leaving many species to starve or struggle for survival.

The consequences extend beyond wildlife. Wildfires have caused devastating human losses, with 88,000 people evacuated and a rising death toll of 25. Meanwhile, the non-human world suffers equally, particularly endangered species with limited ranges. Red-legged frogs, reintroduced into Santa Monica streams in 2014, are among the most affected, with their habitats repeatedly destroyed. The Woolsey Fire of 2018 was followed by mudslides that wiped out much of the region's delicate ecosystem, and scientists fear similar outcomes this time. California newts, reptiles, and snakes are also at high risk, while mammals and birds, although more likely to escape, face challenges in finding food and shelter as the ecosystem bounces back.

Despite the devastation, hope remains. The chaparral is a fire-adapted ecosystem, and life often endures beneath the soil. Seeds can survive and germinate quickly, with grasses sprouting weeks after the first rain. Shrubs may take up to a decade to recover, depending on rainfall. Prof. Stefan Doerr, an expert on wildfires, emphasizes the resilience of this landscape, noting its evolutionary adaptation to high-intensity fires occurring every 30 to 100 years. While the aftermath looks bleak, these fires play a role in maintaining biodiversity, offering a glimmer of hope for recovery.

Which of the following can be inferred from the passage?

Phương án nào sau đây chỉ ra vai trò của mạch tích hợp trong kĩ thuật điện tử?

Hợp chất có công thức cấu tạo nào sau đây là alcohol?

Read the following passage about home schooling in the UK 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.

Full-time education in the UK is compulsory from the age of five to sixteen, but this doesn’t have to be in a school. Around 50,000 children are educated at home. This is called ‘homeschooling’.

 Parents take their children out of school for different reasons, like illness and the need for special care, or because the distance to the nearest school may be too far. Some children are simply unhappy at school. Whatever the reason, they’re allowed to study at home, although inspectors regularly check how they are getting on.

 Hayley and Jenny haven’t been to school for two years but they haven’t neglected their studies. Their mother worked out strict timetables for them, with hourly lessons for each day. She’s responsible for teaching them Maths, English, History and French. Their father teaches them Science and Geography. They study all the other school subjects online. ‘We have lessons with Dad in the evenings and at weekends,’ explains Hayley.

 The family’s home is in a remote part of Wales. ‘The girls were fine at school but they spent so much time getting to school, they were too tired to learn, says their mother, Julia”. ‘We had a family conference and in the end we decided to try homeschooling. So far, it’s been a big success, but the girls know that if they want to go back to school at any time, we’ll let them. We follow the normal school program of lessons, and they will take all the normal school exams.’

 There are disadvantages too, of course. ‘Social isolation is something I worry about,’ says Julia. They both seem happy and well-adjusted, but they haven’t really got friends who live locally. But in the summer holidays they go away on trips to summer camps, where they have no trouble mixing with people and making friends.’

Which of the following is TRUE according to the passage?

Ngành công nghiệp truyền thống của Liên bang Nga là gì?

Read the following leaflet and mark the option that best fits the numbered blanks from 19 to 24. 

TIPS FOR BETTER TIME MANAGEMENT

Want to get more done in less time? Follow these strategies for improving your productivity and focus!

Common Struggles: 

Many people (19) _____ effective time management, leading to stress and unfinished tasks. Research shows that nearly 70% of workers feel overwhelmed by their workload.

Actionable Solutions!

- Prioritize your tasks! Start by making a to-do list and (20) _____ with the most important tasks first.

- Break down big projects! Tackling a large project can be daunting, but breaking it into smaller, (21) _____ parts helps ensure progress without feeling overwhelmed.

- Avoid distractions! (22) _____ multitasking, focus on one task at a time to (23) _____ your efficiency.

- Take breaks! Give yourself regular breaks to rest and recharge, (24) _______ can help maintain a higher level of productivity.

Nhóm A bao gồm các

Mark the letter A, B, C, or D on your answer sheet to indicate the word(s) OPPOSITE in meaning to the underlined word(s) in each of the following questions.

The travel agent gave us such diverse choices of destinations all over the country that we couldn't make up our minds.

Một vật dao động điều hòa với phương trình $x=10\cos4\pi\left(\dfrac{t}{2}-\dfrac{1}{16}\right)$ ($x$ tính bằng cm, $t$ tính bằng s). Tần số dao động của vật là

Find the word which has a different stress pattern from the other.

Điều gì đã tạo nên nếp sống thanh lịch của người Hà Nội?

Hình ảnh nào cho thấy cây bị héo do nắng nóng?