Khi nam châm quay với tốc độ không đổi, trong dây quấn mỗi pha của máy phát điện xuất hiện sức điện động?

A. Một chiều

B. Xoay chiều một pha

C. Xoay chiều ba pha

D. Đáp án khác

Read the following passage and answer the questions

I’m Senka. I always wish to have a motorhome in my life. My motorhome will not need to be big, but it might have everything I need inside. There will be 4 rooms in it: a living room, a kitchen, a bedroom and a toilet. There is a small sofa and a lovely table in the head of the car. This will be the place for my friends when they visit me. It's like a living room. The biggest part of my motorhome will be a kitchen. It will be in the middle of the car. There will be an automatic dishwasher, a modern fridge, a small oven and an automatic washing machine in the kitchen. A small toilet will be in the kitchen too. The last part will be my bedroom, also my entertainment place. There will be a small bed, a wireless TV and a hi-tech computer. Everything might be small in my motorhome. It would be a fantastic if I had my own motorhome. The best thing about having a motorhome is that I can drive it myself and travel around.

How many rooms will there be in the house?

Hợp chất hữu cơ mạch hở X có công thức phân tử C 6 H 10 O 4 . Thuỷ phân X tạo ra hai ancol đơn chức có số nguyên tử cacbon trong phân tử gấp đôi nhau. Công thức của X là

A. C H 3 O C O - C H 2 - C O O C 2 H 5 . 

B.  C 2 H 5 O C O - C O O C H 3 . 

C.  C H 3 O C O - C O O C 3 H 7 . 

D.  C H 3 O C O - C H 2 - C H 2 - C O O C 2 H 5 .  

Cho elip (E) đi qua điểm A(-3;0) và có tâm sai e = 5/6. Tiêu cự của (E) là:

A. 10

B. 5/3

C. 5

D. 10/3

Tìm các giá trị của tham số m để x2 - 2x - m ≥ 0 ∀x

A. m ≤ 0

B. m < 0

C. m ≤ -1

D. m < -1

Read the passage

   Travelling in the future will be much easier and safer.

   People may travel in a driverless car. Even old or disable people will be able to use it because the car can drive itself. However, a driveless car will be expensive.

   People can choose to go on foot on moving pavements. A Swiss company has invented a system of high- speed moving pavements. People will go through the streets at up to 15 km per hour just by standing on the pavements. This will reduce travelling time of pedestrians and traffic jams effectively. Therefore, more people will leave their vehicle home.

Tick T/F

People can go through the streets at up to 50 kph just by standing on the pavements

Choose the best answer to complete the sentences

We should have a ……………… check-up every six months.

A. medical

B. medicine

C. hospital

D. aspirin

Birthday is a family……………………….      (CELEBRATE)