Ta có ab = 3.a.b
=> 10. a +b = 3.a.b
=> 10. a= b chia hết cho a
Vậy a chia hết cho b

Dãy gồm các dung dịch đều tác dụng với Cu(OH)2 là

A. glucozơ, glixerol, ancol etylic

B. glucozơ, andehit fomic, natri axetat

C. glucozơ, glixerol, axit axetic

D. glucozơ, glixerol, natri axetat

I. Choose the correct answer.

Hi. My name is John. I live in Liverpool. Liverpool is a large city in the north of England. I live with my parents, my two brothers and my sister. We live in a large house.

In our house, there is a big kitchen, a dining room, a large living room and a toilet. There is also a separate room for our washing machine and freezer. Upstairs there are five bedrooms, two bathrooms, and another toilet. Outside, there is a large garden. There are two garages.

Where does John live?

A. In England.                 B. In Wales                C. In Scotland.               D. In France.

How many people are there in John's family?

A. 4                               B. 5                                  C. 6                                   D. 7

How many rooms are there in John's house?

A. 10                            B. 11                               C. 13                                    D. 14

Dining room is the room in the house where you ...........................................

A. usually relax in comfortable chairs                                B. eat meals

C. cook food and wash dishes                                          D. wash your body

Which of the following is NOT true?

A. John's family live in a large house.                         B. John's house is big but doesn't have any gardens.

C. The kitchen in John's house is big.                        D. John's house has two garages.