Nguyên tử iron (sắt) có 26 proton.
a) Điện tích hạt nhân của nguyên tử iron là .
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Một chất điểm dao động điều hòa. Khi vật chuyển động từ vị trí biên về vị trí cân bằng thì
Hệ thống chính trị Việt Nam có các đặc điểm nào sau đây?
AYVP, or “ASEAN Youth Volunteer Program,” is a special program for young people in the ASEAN region (a group of Southeast Asian countries). It helps them get (631) ____________ and make a difference. This program (632) ____________ together young people from different ASEAN countries to work together, promote cross-cultural understanding, and develop leadership skills.
AYVP is also designed to address social issues of concern in ASEAN AYVP’s main goal is to help young people feel connected to the ASEAN community and encourage them to work together to solve problems. (633) ____________ helps them not only gain valuable hands-on experience in volunteer work but also build lasting friendships and networks with their (634) ____________ from neighboring countries. This helps them feel responsible for improving the region.
Overall, the ASEAN Youth Volunteer Program shows (635) ____________ for young people to solve big problems. By giving young people the chance to make positive changes, AYVP helps the ASEAN community grow stronger and creates a better future for everyone.
Phenol được tổng hợp từ cumene (isopropylbenzene) bằng phản ứng oxi hóa bởi oxygen rồi thủy phân trong môi trường acid thu được hai sản phẩm là phenol và acetone theo phương trình hóa học sau:
Người ta tiến hành điều chế phenol từ 2 tấn cumene. Khối lượng phenol điều chế được từ lượng cumene trên là (Biết hiệu suất phản ứng là \(90 \%\) ).
Yếu tố quan trọng nhất quyết định tính đa dạng và đặc thù của protein là
Trình độ lao động ở nông thôn nước ta có xu hướng tăng lên là nhờ
Ngân sách nhà nước có vai trò như thế nào trong việc duy trì hoạt động của bộ máy nhà nước?
Một công ty chuyên sản xuất đồ gia dụng ước tính chi phí để sản xuất x (sản phẩm) là: \(C(x)=2x+50\) (triệu đồng), khi đó \(G(x)=\frac{C(x)}{x}\) là chi phí sản xuất cho mỗi sản phẩm. Xem G(x) là một hàm số xác định trên \(\left( \left. 0;+\infty \right) \right.\), số tiệm cận ngang của đồ thị hàm số G(x) là
Read the following passage about the impact of social media on mental health 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.
[I] In recent years, social media platforms have become a central part of daily life, offering users countless ways to connect, share, and communicate. [II] While these platforms offer many advantages, experts have noted rising concerns about their effects on mental health, particularly among young people (Smith & Anderson, 2018). [III] Studies reveal that excessive social media use can contribute to feelings of anxiety, depression, and loneliness, despite its intention to promote connection and social interaction (Twenge & Campbell, 2019). [IV]
A primary reason for these mental health concerns is the tendency for social media users to compare themselves to others. Platforms like Instagram and Facebook often highlight idealized lifestyles, leading users to feel inadequate about their own lives. Additionally, the constant notifications and messages contribute to a "fear of missing out," or FOMO, which keeps individuals in a cycle of checking their phones, often reducing the quality of sleep and overall well-being.
There is also a growing body of research suggesting a link between social media use and decreased attention spans. When users frequently switch between apps and notifications, their ability to focus for extended periods may diminish (Rosen, 2019). This shift in attention can interfere with productivity, especially in academic and professional settings, where sustained focus is essential.
Addressing these challenges requires a multi-faceted approach. Some mental health professionals suggest limiting screen time and setting boundaries, such as "device-free" hours before bedtime. Others recommend engaging in offline activities, like reading or exercising, to reduce dependence on social media and build healthier habits. According to psychologists, such strategies can enhance mental resilience and allow for more meaningful, balanced relationships (Robinson & Smith, 2020).
Which of the following best summarizes the passage?
Xác định một từ/cụm từ SAI về mặt ngữ pháp/ hoặc ngữ nghĩa/logic/phong cách.
Trong vũ trụ, nếu chỉ riêng loài người biết mình có đời sống tinh thần cao vượt lên trên hết vạn vật; có lí trí phân biệt thị phi, thiện ác, quan niệm được tận thiện, tận mĩ để ngày ngày hướng về chỗ chí thiện ấy mà cố sức tiến lên.
Trong bảng mã Unicode Tiếng Việt, mỗi kí tự được biểu diễn bởi bao nhiêu byte?
Cho hình chóp \(\mathrm{S}. \mathrm{ABCD}\) có đáy \(ABCD\) là hình bình hành. Mặt phẳng \((\alpha)\) qua \(BD\) và song song với \(SA\), mặt phẳng \((\alpha)\) cắt \(SC\) tại \(K\). Tính tỉ số \(\frac{S K}{K C}\).
Nhà thơ đã bao quát cảnh thu như thế nào?
Read the following passage about the impact of social media on mental health 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.
[I] In recent years, social media platforms have become a central part of daily life, offering users countless ways to connect, share, and communicate. [II] While these platforms offer many advantages, experts have noted rising concerns about their effects on mental health, particularly among young people (Smith & Anderson, 2018). [III] Studies reveal that excessive social media use can contribute to feelings of anxiety, depression, and loneliness, despite its intention to promote connection and social interaction (Twenge & Campbell, 2019). [IV]
A primary reason for these mental health concerns is the tendency for social media users to compare themselves to others. Platforms like Instagram and Facebook often highlight idealized lifestyles, leading users to feel inadequate about their own lives. Additionally, the constant notifications and messages contribute to a "fear of missing out," or FOMO, which keeps individuals in a cycle of checking their phones, often reducing the quality of sleep and overall well-being.
There is also a growing body of research suggesting a link between social media use and decreased attention spans. When users frequently switch between apps and notifications, their ability to focus for extended periods may diminish (Rosen, 2019). This shift in attention can interfere with productivity, especially in academic and professional settings, where sustained focus is essential.
Addressing these challenges requires a multi-faceted approach. Some mental health professionals suggest limiting screen time and setting boundaries, such as "device-free" hours before bedtime. Others recommend engaging in offline activities, like reading or exercising, to reduce dependence on social media and build healthier habits. According to psychologists, such strategies can enhance mental resilience and allow for more meaningful, balanced relationships (Robinson & Smith, 2020).
The word "their" in paragraph 3 refers to ____.
Choose A, B, C or D to complete each sentence.
According to the chairman's spokesperson, further ______________ in the marketing division are to be expected.
Trong mặt phẳng toạ độ \(Oxy\), cho hai điểm \(A(1;5),B(3;2)\). Điểm \(C\) đối xứng với \(A\) qua \(B\). Toạ độ điểm \(C\) là?
Read the passage carefully. Choose an option (A, B, C or D) that best answers each question from 23 to 30.
1. How do children learn about wildlife? And is what they learn the sort of thing they should be learning? It is my belief that children should not just be acquiring knowledge of animals but also developing attitudes and feelings towards them based on exposure to the real lives of animals in their natural habitats. But is this happening?
2. Some research in this area indicates that it is not. Learning about animals in school is often completely disconnected from the real lives of real animals, with the result that children often end up with little or no understanding or lasting knowledge of them. They learn factual information about animals, aimed at enabling them to identify them and have various abstract ideas about them, but that is the extent of their learning. Children's storybooks tend to personify animals as characters rather than teach about them.
3. For direct contact with wild and international animals, the only opportunity most children have is visiting a zoo. The educational benefit of this for children is often given as the main reason for doing it but research has shown that zoo visits seldom add to children's knowledge of animals – the animals are simply like exhibits in a museum that the children look at without engaging with them as living creatures. Children who belong to wildlife or environmental organizations or who watch wildlife TV programmes, however, show significantly higher knowledge than any other group of children studied in research. The studies show that if children learn about animals in their natural habitats, particularly through wildlife-based activities, they know more about them than they do as a result of visiting zoos or learning about them in the classroom.
4. Research has also been done into the attitudes of children towards animals. It shows that in general terms, children form strong attachments to individual animals, usually their pets, but do not have strong feelings for animals in general. This attitude is the norm regardless of the amount or kind of learning about animals they have at school. However, those children who watch television wildlife programs show an interest in and affection for wildlife in its natural environment, and their regard for animals in general is higher.
What can be inferred from paragraph 4 about children's attitudes to animals?
Chăn nuôi công nghiệp là gì ?
Kí hiệu nào sau đây viết đúng mệnh đề: “\(\sqrt 2 \) không là số hữu tỉ”?
Một lượng khí hydrogen có \({T_1} = 500\;{\rm{K}},{p_1} = {10^5}\;{\rm{N}}/{{\rm{m}}^2}\) được làm nóng đến \({T_2} = 1000\;{\rm{K}}.\) Coi thể tích, khối lượng khí hydrogen không đổi. Tìm áp suất \({p_2}\) của khí hydrogen.