Khảo sát thời gian sử dụng điện thoại một ngày của học sinh lớp 12A thì được mẫu số liệu ghép nhóm sau:

Thời gian (phút)	\(\)\(\left[ {0\,;\,20} \right)\)	\(\left[ {20\,;\,40} \right)\)	\(\left[ {40\,;\,60} \right)\)	\(\left[ {60\,;\,80} \right)\)	\(\left[ {80\,;\,100} \right)\)
Số học sinh	2	5	7	19	9

Độ lệch chuẩn của mẫu số liệu ghép nhóm trên thuộc khoảng nào dưới đây?     

Read the following passage about green living habits 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.

     In an era marked by climate change and environmental degradation, adopting green living habits has become increasingly vital. Green living refers to a lifestyle that seeks to minimize one’s ecological footprint through conscious choices in daily activities. This can include everything from reducing waste to conserving energy and using sustainable products. As more individuals recognize the importance of preserving our planet, the movement toward greener practices continues to gain momentum. 

     One of the most significant aspects of green living is its focus on sustainability. By choosing products that are eco-friendly, consumers can support businesses that prioritize environmental responsibility. For instance, using reusable bags, bottles, and containers reduces plastic waste and promotes a circular economy. Furthermore, opting for locally sourced foods not only supports local farmers but also decreases the carbon emissions associated with transportation.

     When green living habits are adopted, they can lead to profound changes in our environment. By reducing their energy consumption through the use of energy-efficient appliances, individuals help lower greenhouse gas emissions. Consequently, this contributes to cleaner air and mitigates the effects of climate change. Moreover, by practicing water conservation methods, such as fixing leaks and using low-flow fixtures, households can significantly decrease water waste, promoting the sustainable use of this precious resource.

     In conclusion, educating individuals about green living habits is crucial for promoting a more sustainable future. Schools and community organizations can offer workshops and resources that highlight the benefits of eco-friendly practices. Additionally, social media campaigns can raise awareness and encourage people to share their experiences with sustainable living. By empowering individuals to make informed choices, we can collectively work toward a healthier planet for generations to come.