Nguyên tử nguyên tố X có số hiệu nguyên tử là 19, số neutron có trong hạt nhân là 20. Kí hiệu nguyên tử X là
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Loại sâu hại nào thuộc họ Muội nâu?
Cho mệnh đề \(P:\) “\({x^2} - 3x + 4 = 0\) vô nghiệm” và các mệnh đề sau.
1/ “\({x^2} - 3x + 4 = 0\) có nghiệm”.
2/ “\({x^2} - 3x + 4 = 0\) có hai nghiệm phân biệt”.
3/ “\({x^2} - 3x + 4 = 0\) không vô nghiệm”.
Có bao nhiêu phát biểu là phủ định của mệnh đề \(P\)?
Phương án nào sau đây là các giá trị dùng để biểu diễn dãy nhị phân?
Cơ sở của sinh sản vô tính ở động vật là quá trình gì?
Đến giữa thế kỉ XIX, thể chế chính trị của Nhật là:
Công ty môi giới việc làm B lựa chọn hồ sơ những người đăng kí để gửi cho các doanh nghiệp, cửa hàng cần người làm việc phù hợp với thông tin trên hồ sơ. Trong trường hợp này, công ty B đang đóng vai trò chủ thể nào của nền kinh tế?
Nội dung nào dưới đây không thể hiện đặc điểm hoạt động của Tòa án nhân dân?
Con hãy lựa chọn đáp án Đúng hoặc Sai
Văn bản Đăm Săn chiến thắng Mtao Mxây là đoạn giữa của sử thi Đăm Săn, đúng hay sai?
Để điều tiết hoa quả trái vụ như cây thanh long, người ta sử dụng phương pháp nào?
Một thang máy có khối lượng 1300 kg được kéo lên theo phương thẳng đứng bằng dây cáp nối với một động cơ như hình 1. Hình 2 là đồ thị biểu diễn sự biến thiên tốc độ \(\text{v}\left( \text{m}/\text{s} \right)\) của thang máy theo thời gian \(\text{t}\left( \text{s} \right)\) (lấy \(\text{g}=9,8\text{ }\!\!~\!\!\text{ m}/{{\text{s}}^{2}}\)).
Lực căng trung bình của dây cáp trong khoảng thời gian từ giây thứ 40 đến giây thứ 50 là bao nhiêu?
Đồ thị hàm số \(y = f\left( x \right) = \left\{ \begin{array}{l}2x + 3{\rm{ }}\,\,\,khi{\rm{ }}x \le 2\\{x^2} - 3{\rm{ }}\,\,\,khi{\rm{ }}x > 2\end{array} \right.\) đi qua điểm có tọa độ nào sau đây?
Xác định chiều cao của một tháp mà không cần lên đỉnh của tháp. Đặt kế giác thẳng đứng cách chân tháp một khoảng \(CD=60\) m, giả sử chiều cao của giác kế là \(OC=1\) m. Quay thanh giác kế sao cho khi ngắm theo thanh ta nhìn thấy đỉnh \(A\) của tháp. Đọc trên giác kế số đo của góc \(\widehat{AOB}={{60}^{\circ }}\).
Tính chiều cao của ngọn tháp. (làm tròn kết quả đến hàng đơn vị của mét).
Đọc đoạn trích sau và trả lời câu hỏi:
Dốc lên khúc khuỷu, dốc thăm thẳm
Heo hút cồn mây súng ngửi trời
Ngàn thước lên cao, ngàn thước xuống
Nhà ai Pha Luông mưa xa khơi.
Anh bạn dãi dầu không bước nữa
Gục lên súng mũ bỏ quên đời!
(Tây Tiến, Quang Dũng)
Biện pháp nghệ thuật nhân hoá trong đoạn trích trên thể hiện nét riêng nào trong vẻ đẹp tâm hồn của người lính Tây Tiến?
Read the following leaflet and mark the letter A, B, C, or D on your answer sheet to indicate the option that best fits each of the numbered blanks from 7 to 12.
Here are some ways to help reduce global warming. Which of these do you regularly do?
Don't use private cars. Your willingness to walk or cycle to nearby places can help reduce the emissions of carbon dioxide and also reduce your own carbon footprint. Use public transport. If travelling long distances, then use public transport rather than your car. However, if you carpool (travel together with a group of people in one car), then you are choosing to help ___(7)___ environment. If we travel with ___(8)___, we will use less petrol.
Make a decision to reduce, recycle, and reuse. Reduce waste by buying reusable products. Don't forget to recycle plastics, glass, and paper products. You may wish to reuse some of your old items to ___(9)___, too. Take unneeded ___(10)___ to a recycling centre.
Buy local goods. When you buy goods ___(11)___ from far-away places, it takes a lot of energy to ___(12)___ them to your area. This means that if you don't buy local food and products, then more emissions of carbon dioxide will happen during the transportation process.
(Adapted from English Discovery)
Read the following passage about education in Nepal 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.
A few years ago, amid a record drought, scientists noticed something odd. A few of California’s giant sequoias inside Sequoia and Kings Canyon National Parks were dying in ways no one had ever documented – from the top down. When researchers climbed into the canopies, they discovered that beetles had bored into a few branches. By 2019, at least 38 of the trees had died – not a large number, but "concerning because we’ve never observed this before,” says Christy Brigham, the park’s chief of resource management.
Scientists had assumed that stately sequoias, with their bug-repelling tannins, were immune to dangerous pests. Worried experts are investigating whether some mix of increased drought and wildfire, both worsened by climate change, have now made even sequoias susceptible to deadly insect invasions.
If so, these ancient sentinels would be just the latest example of a trend experts are documenting around the world: Trees in forests are dying at increasingly high rates—especially the bigger, older trees. According to a study in the journal Science, the death rate is making forests younger, threatening biodiversity, eliminating important plant and animal habitat, and reducing forests’ ability to store excess carbon dioxide generated by our consumption of fossil fuels. [A]
There is no single direct cause. Decades of logging and land clearing play a role, scientists say. But increasing temperatures and rising carbon dioxide from the burning of fossil fuels have significantly magnified most other causes of tree death. Scientists are documenting longer and harsher droughts, more severe outbreaks of insects and disease, and increasingly catastrophic wildfires.
With 60,000 known tree species on Earth, those shifts are playing out differently across the planet. In central Europe, for instance, “You don’t have to look for dead trees,” says Henrik Hartmann, with Germany's Max Planck Institute for Biogeochemistry. “They’re everywhere.” In one recent year, following a week of excessive heat, hundreds of thousands of beech trees dropped their leaves. Even in colder regions, “You get a couple of hot years and the forests are suffering,” says Hartmann. “There are individual species that are being driven beyond the threshold of what they can handle.” [B]
Just last year, massive fires marched through a dry Australia, smoldered across 7.4 million acres in northern Siberia, and focused the world’s attention on blazes in the Amazon.
The consequences of all these changes around the world are still being assessed. The first national look at tree mortality in Israel showed vast stretches disappearing, thanks largely to scorching heat and wildfires. [C] In a country largely blanketed by stone and sand, forests mean a great deal. Trees support nests for eagles and habitat for wolves and jackals. They hold soil with their roots. [D]
“We’re dealing with a very tough situation. It’s a race to the unknown,” says Tamir Klein at the Weizmann Institute of Science.
What does ‘these ancient sentinels’ in paragraph 3 refer to?
Sinh vật nào sau đây được sử dụng để thu nhận Streptokinase?
Anh An mua ô tô trả góp trị giá 400 triệu với lãi suất \(1.2 \%\) một tháng. Hỏi hàng tháng anh An phải trả bao nhiêu triệu để sau 4 năm thi hết nợ.
*Làm tròn đến hàng đơn vị.
Ưu điểm của nhà kính đơn giản là:
Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer.
Why are we always pointing to Instagram as the cause of mental illness in our teenagers? It’s frustrating that abusive relationships, and the trauma they cause, are rarely mentioned in discussions about the prevalence of mental health problems in young people. Research by Women’s Aid and Cosmopolitan has found that a third of teenage girls have been in an abusive relationship. And, if that isn’t shocking enough, when the remaining two-thirds were asked further questions, it emerged that 64% of them had, in fact, experienced abusive behaviour – they just didn’t realise it was abuse.
Domestic abuse is normally associated with women cowering on the floor, as a violent husband waits to strike, or mothers covering up their black eyes with concealer before the school run. On the same day that the domestic abuse bill received its second reading in parliament, Age UK called for action to tackle domestic abuse of over-60s, whose needs it says are often overlooked by the law, policy and practice. The needs of teenagers in the heady throes of first love who are in emotionally abusive relationships also need to be recognised.
Common themes of such relationships include (though are not limited to) excessive jealousy, repeated criticism and sexual coercion. If your boyfriend or girlfriend is checking your phone, constantly asking to know your whereabouts, getting upset when you spend time away, turning up unannounced to surprise you, these are all examples of coercive control. If they never apologise in an argument and make everything your fault, tell you what you can and can’t wear, undermine you and/or publicly humiliate you under the guise of a “joke”, these again are common instances of controlling behaviour. Ditto, if they have a Jekyll/Hyde personality, make you feel like you are walking on eggshells even when things are seemingly going well, and threaten to hurt themselves if you leave. When it comes to sexual coercion and rape, examples include making you feel pressured to perform sexual acts you’re uncomfortable with, such as sending nude photos, having sex before you’re ready, being pressured to re-enact extreme sex from porn films or being told you don’t love them if you say no.
Often the victim in an abusive relationship can never quite put their finger on one thing, but the overwhelming feeling is of a general unease, feeling unsafe, defective, wrong, scared and as if you are going crazy. It’s your “yourselfness” that’s being consistently undermined, controlled and attacked by the person who claims to love you.
Which of the following is closest in meaning to “prevalence” as used in the passage?
Nhóm động vật nào dưới đây là động vật hoang dã