để diện tích hình tròn giảm đi bốn lần diện tích ban đầu thì độ dài bán kính của hình tròn đó phải giảm đi bao nhiêu lần so với độ dài ban đầu? giải chi tiết một em với ạ

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1. Where ___________you (live)____________? I (live)______________in Hai Duong town. 2. What _______________he (do) ______________now? He (water)_________________flowers in the garden. 3. What _______________she (do)_____________? She (be)______________a teacher. 4. Where _________________you (be) from? 5. At the moment, my sisters (play) ____________ volleyball and my brother (play) ______________soccer. 6. It is 9.00; my family (watch)___________________TV. 7. In the summer, I usually (go) ______________ to the park with my friends, and in the spring, we (have) ___________Tet Holiday; I (be) ________ happy because I always (visit) ______________ my granparents. 8. ____________your father (go)_____________to work by bus? 9. How ___________your sister (go)___________to school? 10. What time _____________they (get up)_________________? 11. What ____________they (do)________________in the winter? 12. Today, we (have)______________English class. 13. Her favourite subject (be)__________________English. 14. Now, my brother (like)_________________eating bananas. 15. Look! Aman (call)_________________you. 16. Keep silent ! I (listen)____________________to the radio. 17. ______________ you (play)_________________badminton now? 18. Everyday, my father (get up)_________________ at 5.00 a.m, but today, he (get up) __________________ at 6.00 am. 19. Every morning , I (watch)_________________tv at 10.00, but today I (Listen) ________________ to music at 10.00. 20. Everyday , I (go) __________to school by bike but today I go to school by motorbike. 21. Every morning, my father (have) ______________a cup of coffe but today he (drink)____________milk. 22. At the moment, I(read)_______________a book and my brother (watch)_______ TV. 23. Hoa (live)________________in Hanoi, and Ha (live)________________in HCM City. 24. Hung and his friend (play)_______________badminton. 25. They usually (get up)___________________at 6.oo in the morning. 26. Ha never (go)______________fishing in the winter but she always (do)_____________ it in the summer. 27. My teacher (tell)__________________Hoa about Math. 28. There (be)____________________ animals in the circus. 29. _______________he (watch)______________TV at 7.00 every morning? 30. What _____________she (do) _________________at 7.00 am? 31. How old _________she (be)? 32. How ___________she (be)? 33. My children (Go)________________to school by bike. 34. We (go)_______________to supermarket to buy some food. 35. Mr. Hien (go)________________on business to Hanoi every month. Nhìn dài dài thôi chứ nó cx k khó mng giúp mình với