Cho ∆EKF nhọn (EK < EF). Gọi I và H lần lượt là trung điểm EK và EF. Dựng T đối xứng F qua I và N đối xứng K qua H.a) Chứng minh KFET là hình bình hành và suy ra TK // EF.b) Chứng minh EN // KFc) Chứng minh T; E và N thẳng hàng.
1. I found out about bombings _____ the internet.
A. at B. in C. on D. above
2. You _____ the washing-up and I’ll do the drying.
A. make B. do C. create D. finish
3. Which musical _____ do you play?
A. instrument B. device C. tool D. appliance
4. The foreign minister admitted he was still _____ about the alarming situation in the country.
A. excited B. anxious C. eager D. surprised
5. I know she’s offered to babysit, but I don’t want her to think we’re taking _____ of her.
A. notice B. opportunity C. chance D. advantage
6. The information _____ the website is free and perfectly legal.
A. on B. at C. in D. about
7. Drug trafficking is a matter of considerable concern for the entire international _____.
A. society B. environment C. community D. culture
8. In those days, it was not _____ for men to wear shirts without ties.
A. acceptable B. accept C. acceptably D. acceptance
9. That is a _____ achievement, but it represents an enormous challenge as well.
A. giant B. high C. great D. strong
10. Sarah was just talking to her friends _____ Simon’s new girlfriend.
A. for B. in C. about D. towards