Các electron của nguyên tố X được phân bố trên 2 lớp, lớp thứ 2 có 7 electron. Số hiệu nguyên tử của nguyên tố X là

Access là phần mềm như thế nào?

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

Their apartment looks nice. In fact, it’s ___________.

Việt Nam Quang phục hội chủ trương dùng biện pháp nào để đánh Pháp?

Read the following passage about Asia’s culture and mark the letter A, B, C or D on your answer sheet to indicate the best answer to each of the following questions

[I] Chemicals are present everywhere in our environment, some of which occur naturally, while others are the result of human activities. [II]. They are found in the air, water, and soil, and can have both positive and negative impacts on the ecosystem. Some chemicals, like nutrients, help support life by promoting plant growth [III]. However, others, especially synthetic chemicals such as pesticides, fertilizers, and industrial waste, can be harmful to both the environment and human health. [IV]

The widespread use of pesticides and fertilizers in agriculture has been a major cause of chemical pollution. When these chemicals are used improperly or excessively, they can wash into rivers, lakes, and oceans, leading to water pollution. This runoff can also contribute to the depletion of oxygen in water bodies, a process known as eutrophication. Eutrophication harms aquatic life, disrupting ecosystems and causing the death of fish and other organisms that rely on oxygen.

Toxic chemicals such as heavy metals (e.g., mercury and lead) pose additional threats to the environment and human health. These substances can accumulate in the food chain, starting from plants and animals in contaminated areas and eventually reaching humans. Long-term exposure to these chemicals can lead to serious health issues, including neurological disorders, cancer, and other chronic conditions. Many countries have established regulations to limit the use of harmful chemicals, but enforcement remains a challenge.

Efforts to reduce chemical pollution involve a combination of government regulations, technological innovations, and public awareness. Governments worldwide have introduced stricter rules on the use of hazardous chemicals and encouraged the development of eco-friendly alternatives. These regulations aim to limit the harmful impact of chemicals on the environment, encouraging industries to adopt safer practices. Environmental organizations play a vital role in monitoring chemical pollution, raising awareness, and advocating for cleaner technologies. They work closely with policymakers to ensure effective enforcement of environmental laws. While progress has been made, ongoing efforts are needed to address emerging challenges and ensure a safer and healthier environment for future generations.

The word "depletion" in paragraph II is OPPOSITE in meaning to ____.

Một vật chuyển động với vận tốc 1m/s có động năng 1J. Khi vật có vận tốc 3m/s thì động năng của vật là

Dialogue arrangement:

a. In that case, I’ll draw you a map.

b. If you can wait five minutes, I’ll walk you there.

c. Where can I get good pho around here?

d. I’m in a hurry and need to leave now.

Một hình lăng trụ có đáy là tam giác đều cạnh a, cạnh bên 2a và tạo với đáy góc $60°$. Ta có thể tích lăng trụ đó bằng?

Chọn câu đúng: Gia tốc là đại lượng

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.

Cho hình bình hành ABCD có \(AB = 8cm\), \(AD = 12cm\) , góc \(\angle ABC\) nhọn và diện tích tam giác ABC bằng \(27{\mkern 1mu} c{m^2}\) Khi đó \(\cos \left( {\overrightarrow {AB} ,\overrightarrow {BC} } \right)\) bằng 

Để nghiên cứu ảnh hưởng của nước lên sự sinh trưởng của cây trồng, bạn An thiết kế 2 chậu cây: ở chậu thí nghiệm, tưới đủ nước; ở chậu đối chứng, không tưới nước. Mô tả này thể hiện bước nào trong tiến trình nghiên cứu khoa học?

Cơ sở để quy định tên gọi, trình tự ban hành của văn bản pháp luật là gì?

Một bình đựng 5 viên bi kích thước và chất liệu giống nhau, chỉ khác nhau về màu sắTrong đó có 3 viên bi xanh và 2 viên bi đỏ. Lấy ngẫu nhiên từ bình ra một viên bi ta được viên bi màu xanh, rồi lại lấy ngẫu nhiên ra một viên bi nữXác suất để lấy được viên bi đỏ ở lần thứ hai bằng bao nhiêu?

Màng sinh chất lõm vào hình thành eo thắt phân chia thành hai tế bào là đặc điểm của quá trình gì?

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.

Everybody gets the same training plan.

Tổng số hạt neutron, proton, electron trong ion $^{35}_{17}Cl^-$ là

Most of the participants can’t help _______ why the president spoke so angrily.

Thực hiện 2 thí nghiệm theo hình vẽ sau:

Ở thí nghiệm nào xuất hiện kết tủa trước?

Cho hình chữ nhật ABCD có AB = 2, AD = 1. Tính góc giữa hai vectơ \(\overrightarrow {AC} \)  và \(\overrightarrow {BD} \)?