Hỗn hợp X gồm Mg, Al, Zn. Cho 6,5 gam hỗn hợp X vào 200 ml dung dịch B a ( O H ) 2 0,5M và KOH 1M, kết thúc phản ứng thu được 4,256 lít khí H 2  (đktc). Nếu cho 13 gam hỗn hợp X tác dụng với một lượng dung dịch H 2 S O 4 loãng đến khi ngừng thoát khí thu được 4,032 lít H 2  (đktc) và chất rắn không tan Y. Cho Y vào 200 ml dung dịch chứa AgNO₃ 1M và C u N O 3 2  2M, sau khi phản ứng xảy ra hoàn toàn thu được 34,4 gam chất rắn X. Thành phần phần trăm số mol của Zn trong X là

A. 40%

B. 26,31%

C. 21,05%

D. 30,25%

Choose the letter A, B, C or D to complete the sentences

“Would you like another cup of coffee?" "I wouldn't _______ no."

A. say

B. tell

C. speak

D. talk

Read the passage below and decide whether the statements are TRUE or FALSE?

We are all around computers. Computers play an important play in our day to day lives, like we are very much dependent them for doing many things including giving users the ability to quickly and easily store and process data. Since the invention of computer they have evolved in terms of increased computing power and decreased size. Computers are used in many sectors like Education, Health and Medicine, Financial Institutions, Transport System, E-Commerce, Defence etc.

Computers connect us to the world of unknown. They help us gathering knowledge and huge information from the internet and storing it. Computers are multitasking and accurate enough to be used almost anywhere and everywhere including banks. Computer provide security from destructive forces and from unwanted action from unauthorized users like cyber attack or access attack.

Now computer is not just a calculating device, it has become much more than that. One of the main advantages of computer is its incredible speed, which helps human to complete their task in few seconds. All the operations can be performed very fast just because of its speed else wise it takes a long time to perform the task.

Question: Computers are not speedy enough to help human to complete their task in few seconds.

A. True

B. False

Choose the letter A, B, C or D the word that has the underlined part different from others.

A. audience

B. biology

C. idol

D. fine

TRẢ BẠN NÀO ĐÚNG

Phương trình có nghiệm là?

A. x = −1; x = 3

B. x = 1; x = −3

C. x = −1

D. x = 3

A. come

B. month

C. mother

D. open