Cho hai đường thẳng \({d_1}:3x - 4y + 5 = 0,{d_2}:4x - 3y + 2 = 0\). Điểm \(M\) nào sau đây cách đều hai đường thẳng trên?

Este X chứa vòng benzen có công thức phân từ là C₈H₈O₂. Số công thức cấu tạo của X là 

Read the passage carefully

1. Millions of people are using cellphones today. In many places, it is actually considered unusual not to use one. In many countries, cellphones are very popular with young people. They find that the phones are more than a means of communication - having a mobile phone shows that they are cool and connected.

2. The explosion in mobile phone use around the world has made some health professionals worried. Some doctors are concerned that in the future many people may suffer health problems from the use of mobile phones. In England, there has been a serious debate about this issue. Mobile phone companies are worried about the negative publicity of such ideas. They say that there is no proof that mobile phones are bad for your health.

3. On the other hand, medical studies have shown changes in the brain cells of some people who use mobile phones. Signs of change in the tissues of the brain and head can be detected with modern scanning equipment. In one case, a traveling salesman had to retire at young age because of serious memory loss. He couldn't remember even simple tasks. He would often forget the name of his own son. This man used to talk on his mobile phone for about six hours a day, every day of his working week, for a couple of years. His family doctor blamed his mobile phone use, but his employer's doctor didn't  agree.

4. What is it that makes mobile phones potentially harmful? The answer is radiation. High-tech machines can detect very small amounts of radiation from mobile phones. Mobile phone companies agree that there is some radiation, but they say the amount is too small to worry about.

5. As the discussion about their safety continues, it appears that it's best to use mobile phones less often. Use your regular phone if you want to talk for a long time. Use your mobile phone only when you really need it. Mobile phones can be very useful and convenient, especially in emergencies. In the future, mobile phones may have a warning label that says they are bad for your health. So for now, it's wise not to use your mobile phone too often.

Choose an option (A, B, C, or D) that best answers each question:

What does the word “they” in paragraph 2 refer to?

Đồ thị tọa độ - thời gian của hai xe 1 và 2 được biểu diễn như hình dưới đây. Hai xe gặp nhau tại vị trí cách vị trí xuất phát của xe 2 một khoảng

Hàm số $y={\left|x\right|}^3-x^2+4$ có tất cả bao nhiêu điểm cực trị? 

Căn cứ vào đâu để phân loại thị trường thành thị trường tư liệu tiêu dùng, thị trường tư liệu sản xuất?

Pháp luật xác lập, ghi nhận các quyền của công dân trong mọi lĩnh vực đời sống xã hội thể hiện vai trò nào của pháp luật đối với đời sống? 

Dãy bit nào sau đây là biểu diễn nhị phân của số 31 trong hệ thập phân?

Khoai tây sinh sản sinh dưỡng bằng bộ phận nào?

Students had better _________ future employment opportunities when choosing their major in college.

Một chất điểm chuyển động có phương trình chuyển động là \(s=-{{t}^{3}}+6{{t}^{2}}+17t\), với \(t\) (s) là khoảng thời gian tính từ lúc vật bắt đầu chuyển động và \(s\) (m) là quãng đường vật đi được trong khoảng thời gian đó. Trong khoảng thời gian \(8\) giây đầu tiên, vận tốc \(v\) (m/s) của chất điểm đạt giá trị lớn nhất bằng bao nhiêu?

Đặc điểm cơ bản của Hiến pháp nước Cộng hoà xã hội chủ nghĩa Việt Nam là gì?

Bệnh tụ huyết trùng trâu bò xảy ra vào thời gian nào trong năm?

Read the following advertisement/announcement and mark the letter A, B, C, or D on your answer sheet to indicate the correct option that best fits each of the numbered blanks from 1 to 6.

DISCOVER THE IPHONE 16

Looking for a smartphone that redefines innovation? The iPhone 16 is the perfect blend (1) ______
cutting-edge technology and sleek design. With its stunning Super Retina XDR display, you’ll experience vibrant colors and incredible detail. Whether you’re capturing photos or streaming videos, this device offers unparalleled performance. Want to enhance your (2) ______? The iPhone 16 features the powerful A16 Bionic chip, (3) ______ lightning-fast speeds for all your tasks. Plus, with its (4) ______, you can stay connected longer without worrying about (5) ______. With the introduction of Apple Intelligence and new AI-driven audio and visual features, Apple has once again pushed the boundaries of what a smartphone can do. Many of the predictions about the iPhone 16 were right on target, and the launch has received an enthusiastic response from the public. Apple has certainly raised the bar and has (6) ______ a new standard for the future of smartphones.

Đại lượng nào dưới đây phải đo bằng phép đo gián tiếp?

Lớp \(10\;A\) có 20 học sinh nam và 25 học sinh nữ. Có bao nhiêu cách chọn một bạn làm lớp phó lao động?

1. Do you find yourself yawning all day at school? You probably need more sleep. However, it is not just how much sleep you get that is important. What you do before bedtime also has a huge effect on how you feel the next day. If you spend time chatting to someone on social media, or reading a book on your e- reader, you are not alone.

2. All devices' screens give out a large amount of blue light, which affects the body's production of the sleep hormone, melatonin, which can change your sleep patterns. So it is not just getting to sleep that becomes hard, but the quality of your sleep also suffers. The result is that you can wake up several times during the night, and have difficulty getting up in the morning.

3. Sleep is food for the brain, so not sleeping well can be a severe problem for anyone, especially for teenagers, because their brains are still developing. When you do not sleep well, it can be difficult to concentrate at school, which makes it harder to learn and get good grades. It can also affect your mood, making you feel sad or anxious.   

4. So, it is clear you should not use your phone before you go to sleep. Why not leave it in another room? Nothing on social media is so important that it cannot wait a few hours! You should rediscover paper books and enjoy feeling tired and sleepy before bedtime rather than wondering why your best friend has not liked your photo! How will you wake up? You do not have to use the alarm on your phone. Go and buy yourself an old-fashioned alarm clock! The negative effects that screen time is having on sleep have been in the news a lot recently, so manufacturers of smartphones and tablets have added a feature to the mobile devices that can help reduce these. Most new phones have a night-time setting that changes the colour of the screen so that it gives out less blue light. If you really cannot avoid going onto social media at bedtime, think about turning on this setting on your phone.

What does the word it in paragraph 4 refer to?

Xét khai triển của biểu thức \({{\left( x-\frac{1}{2} \right)}^{9}}\).

Chọn số vào vị trí phù hợp:

a) Số hạng không chứa \(x\) trong khai triển là: (…a…).

b) Hệ số của \(x\) trong khai triển là: (…b…).

c) Tổng các hệ số của khai triển là: (…c…).

Câu nào sau đây không đúng?