Câu 1: Thế nào là chuyển động cơ học? Cho ví dụ, chỉ rõ vật làm mốc.

Câu 2: Nêu tính tương đối giữa chuyển động và đứng yên. Cho ví dụ.

Câu 6: Giải thích các hiện tượng:

a. Xe đứng sau đó chạy người ngã về phía sau.
b. Khi dọng cán xuống nền thì lưỡi búa lại đi sâu vào trong cán.

c. Bút tắc mực rẩy mạnh thì mực văng ra ngoài.

cho hai số x,y thõa mãn |x + 2| + |y - 1| = 0

Write a passage about 30-40 word:

What should we do to have the environment less pollution

Ai có đề kiểm tra HK2 2019-2020 không ạ?
Cho e tham khảo

Ai sửa và lược bỏ vài từ giùm em với ạ!

For detective fans, Detective Conan is a series we should not ignore, it has attracted millions of readers from around the world. The main plot is about a high school detective Shinichi Kudo. When he was chasing some suspicious people, he was attacked and poisoned. The pill did not kill him, but it turned him into a six year old boy. Since then, he has lived in a lover's house with a new name. He has a group of friends at school, and together they create the Detective group of class 1B. He has solved many difficult criminal cases under the name of detective Mori Kogoro. Thanks to Dr. Agashi's modern equipment, he is able to put Mori to sleep and use his voice to expose the crime. While living as a first-grade boy, Conan continued to find the true faces of the people who poisoned him. These books still attract a lot of readers even though the series has lasted about 20 years. Detective Conan is one of the best detective series, and it's a shame we missed it.