Cho 86,3g hỗn hợp X gồm Na, K, Ba và Al₂O₃ (trong đó oxi chiếm 19,47% về khối lượng) tan hết vào nước, thu được dung dịch Y và 13,44 lít H₂ (đktc). Cho 3,2 lít dung dịch HCl 0,75M vào dung dịch Y. Sau khi các phản ứng xảy ra hoàn toàn, thu được m gam kết tủa Giá trị của m là

A. 10,4.

B. 27,3.

C. 54,6

D. 23,4

Mark the letter A, B, C, or D on your answer sheet to indicate the underlined part that needs correction in each of the following questions.

As far as I’m (A) concerned, it was (B) the year 2007 (C) which Vietnam joined (D) the World Trade Organization.

A. concerned

B. the year 2007

C. which 

D. the 

Mark the letter A, B, C, or D on your answer sheet to indicate the sentence that best combines each pair of sentences in the following questions.

She was the first woman in the Philippines. She was elected as the president of the country.

A. She was the first woman to be elected as the president of the Philippines. 

B. She was the first woman who is elected as the president of the Philippines. 

C. She was the first woman being elected as the president of the Philippines. 

D. She was the first woman elected as the president of the Philippines.