Vì khối lượng mol của Hidro nhẹ hơn không khí

\(M_{H_2}\left(2\right)< M_{kk}\left(29\right)\)

Chúc bạn học tốt 

1. I would like you to help me to put the chairs away.
=> Would you mind helping me to put the chairs away?
2. People recycle old car tires to make shoes and sandals.
=> Old car tires are recycled to make shoes and sandals by people
3. The boy is playing chess with you. He is my uncle.
=> The boy who is playing chess with you is my uncle
4. Keeping the environment clean is very important.
=> It’s very important to keep the environment clean

Chúc bạn học tốt! 

Sửa lại: That is the man who told me the bad news

Chúc bạn học tốt! 

Chúc bạn học tốt !