Cho hình lăng trụ đứng ABC.A’B’C’ có một đáy là tam giác ABC vuông tại A; AB = 3a,BC = 5a. Biết khối trụ có hai đáy là hai đường tròn nội tiếp hai tam giác ABC, A’B’C’ và có thể tích bằng 2 π a 3 . Chiều cao AA’ của lăng trụ bằng

A. 3a

B.  3 a

C. 2a

D.  2 a

Vật thể nào trong các vật thể sau không phải khối đa diện?

A. 

B. 

C. 

D. 

Bài này áp dụng dãy tỉ số bằng nhau đó bạn

Complete the passage by filling each blank with the correct form of the word in brackets.

    Some people ask me if I like living in my hometown. The answer is certainly ‘yes’. The simple reason is that it has lots of interesting places. If you want to widen your knowledge of the past, you can go to the museum. It's a historical building, with a big collection of (17. value)________ artefacts. There is also a craft village in my hometown. There, the (18. village)________ make    drums. Their drums are not only famous in the locality but also (19. nation)_________.       You can visit the old workshop, where drums are still made in the (20. tradition)_________ way. Some of them are huge! Another attraction in my hometown is the local library. It's an educational place where anyone can borrow books and take them home to read. Besides, it also has a (21. read)________ club. I'm one of its members, and we gather once a week to discuss what we've read together. My hometown is also a cultural centre, with many traditional festivals and (22. act)________. I love it very much.

Question 21:

Mk nè

9,8