199 ạ

C

Gọi x, y lần lượt là số sản phẩm loại I và loại II được sản xuất ra.

Điều kiện x, y nguyên dương.

Ta có hệ bất phương trình sau: 3x+2y≤180

                                                    x+6y≤220

                                                      x>0 y>0

Tiền lãi trong một tháng của xưởng là T = 0,5x+0,4y (triệu đồng).

Ta thấy T đạt giá trị lớn nhất chỉ có thể tại các điểm A, B, C.

Vì C có tọa độ không nguyên nên loại.

Tại A(60;0) thì T = 30 triệu đồng . Tại B(40:0) thì T = 32 triệu đồng.

Vậy tiền lãi lớn nhất trong một tháng của xưởng là 32 triệu đồng.

Đáp án đúng là B. concluding.

Cấu trúc đúng ở đây là: In concluding, I'd like to express my thanks... (Khi kết thúc, tôi muốn bày tỏ lòng biết ơn...).

Giải thích:

A.

1.We use this form when we plan or intend to do something in the future, but there isn’t an exact date or time yet.
→ be going to

2.We use this form when we have organised something and there is an exact date or time.
→ Present continuous

3.We use this form for things which have a fixed timetable.
→ Present simple

4.We use this when we make a prediction about the future.
→ will

D

I would love to visit Tokyo, the bustling capital of Japan. Located on the eastern coast of the country, it offers a blend of modern skyscrapers and traditional temples. The weather is varied, with mild springs, hot summers, and cool winters. Tokyo is famous for its advanced technology, rich culture, and delicious cuisine like sushi and ramen. I want to visit Tokyo to experience its unique mix of tradition and innovation, explore its beautiful parks, and enjoy the vibrant atmosphere of the city.

Smart cities are becoming increasingly popular in cities and pervasive space worldwide. The term refers to the application of technology in urban development, including the installation of sensors, cameras, and other intelligent systems to facilitate data analysis and improve city infrastructure management and maintenance. Smart cities can also improve the quality of life for residents by enhancing public safety, increasing efficiency, and providing greater access to public services. While the concept of smart cities is relatively new, the potential for increased sustainability in urban management and maintenance is significant. By deploying smart systems, cities can optimize waste management, reduce energy consumption, and prioritize resources based on real-time data and analysis. This can lead to better service delivery and improved performance in city services, including transportation, planning, and utilities.

1.The girl ironed the clothes in the afternoon.

Passive: The clothes were ironed by the girl in the afternoon.

2.The employee has signed the contract.

Passive: The contract has been signed by the employee.

3.I am sweeping the floor.

Passive: The floor is being swept by me.

4.Is the dog eating its snack?

Passive: Is the snack being eaten by the dog?