Câu 11: làm lạnh 1lượng chất lỏng thù khối lượng riêng và trọng lượng riêng của chất đó thay đổi như thế nào? A.cả khối lượng riêng và trọng lượng riêng đều tăng B.khối lượng riêng tăng và trọng lượng giảm C.trọng lượng riêng và khối lượng riêng ko đổi D.khối lượng riêng giảm ,trọng lượng riêng tăng Mik đag cần gấp!

rút gọn A= 2 ^12 . 3^5 - 4^6 . 9^2/(2^2 . 3)^6 -- 5^10 . 7^3 - 25^5 . 49^2/(125 . 7)^3 + 5^9 . 14^3

em xin cách làm phép tính này với ạ

1.Kể tên 15 dân tộc Việt Nam 2.Kể 5 phong tục ở thái bình

Read the passage and choose the best answers. People need to breathe. If they don't breathe, they (1)............ die. But how to clean the air people breathe? If they breathe (2)............ air, they will have breathe problems and become (3)........... Plants and animals need clean air, too. A lot of things in our lives create harmful gases and (4)............. the air dirty like cars, motorbikes and factories. Dirty air is called polluted air. 1. * A. must B. will C. are D. is 2. * A. clean B. clear C. dirty D. pollution 3. * A. cycling B. strong C. better D. ill 4. * A. make B. get C. let D. give Choose the letter A, B, C or D to indicate the correct answer to each of the following questions. Question 5 --> 17 5. This is ____expensive dictionary I have. * A. more B. most C. the more D. the most 6. Huy ____learnt English for 5 years. * A. have B. to have C. having D. has 7. Her mother and cousins like ____aerobics to be healthy. * A. going B. doing C. playing D. watching 8. Last night, I ____my favourite food with my friends at school. * A. eat B. ate C. eaten D. did ate 9. People will ____on the moon in the future. * A. living B. live C. are live D. be live 10. It is ____to talk to Mr Wilson. * A.comfort B. comfortable C. comforted D. comfortably 11. In the future, robots will help us ______ the children . * A. look out B. look at C. look after D. look in 12. We ______ go to the concert when the rain stops. We don’t know for sure. * A. might B. would C. can D. will 13. If he ______ so hungry, he will eat that cake. * A. is B. are C.be D. are 14. We might have a ______ TV so we can watch TV programmes from space. * A. wire B. wireless C. wiring D . wires 15. In the future , I will live ______ because I like swimming. * A. in the mountain B. on the Moon C. on the ocean D. under the ground 16. ______ do you go to school? Every afternoon. * A. How much B. How often C. How many D. How 17. ______ pen is this? Can I borrow it? * A. Whose B. whom C. who D. which Choose the letter A, B, C or D to indicate the word whose underlined part is pronounced differently from that of the rest in each of the following questions. QUESTION 18-19-20 18. "OU" * A. OUr B. cOUld C. wOUld D. shOUld 19. "I" * A. lIve B. hIgh C. fInd D. prIce 20. "O" * A. sOn B. Old C. cOld D. tOld nhanh giúp mình với có 15p thôi nhanh với đúng nhé mình càm ơn

với giá trị nào của x thì căn thức sau có nghĩa giúp mk với mn

Mn ới giúp mình với, mình chỉ cần câu iii thôi !

Và bài tập 20: Tính nhanh: A = 978^2 +22^2 + 978 x 44 B = 821^2 + 321^2 - 821 X 642

Read the passage and choose the best answers. People need to breathe. If they don't breathe, they (1)............ die. But how to clean the air people breathe? If they breathe (2)............ air, they will have breathe problems and become (3)........... Plants and animals need clean air, too. A lot of things in our lives create harmful gases and (4)............. the air dirty like cars, motorbikes and factories. Dirty air is called polluted air. 1. * A. must B. will C. are D. is 2. * A. clean B. clear C. dirty D. pollution 3. * A. cycling B. strong C. better D. ill 4. * A. make B. get C. let D. give Choose the letter A, B, C or D to indicate the correct answer to each of the following questions. Question 5 --> 17 5. This is ____expensive dictionary I have. * A. more B. most C. the more D. the most 6. Huy ____learnt English for 5 years. * A. have B. to have C. having D. has 7. Her mother and cousins like ____aerobics to be healthy. * A. going B. doing C. playing D. watching 8. Last night, I ____my favourite food with my friends at school. * A. eat B. ate C. eaten D. did ate 9. People will ____on the moon in the future. * A. living B. live C. are live D. be live 10. It is ____to talk to Mr Wilson. * A.comfort B. comfortable C. comforted D. comfortably 11. In the future, robots will help us ______ the children . * A. look out B. look at C. look after D. look in 12. We ______ go to the concert when the rain stops. We don’t know for sure. * A. might B. would C. can D. will 13. If he ______ so hungry, he will eat that cake. * A. is B. are C.be D. are 14. We might have a ______ TV so we can watch TV programmes from space. * A. wire B. wireless C. wiring D . wires 15. In the future , I will live ______ because I like swimming. * A. in the mountain B. on the Moon C. on the ocean D. under the ground 16. ______ do you go to school? Every afternoon. * A. How much B. How often C. How many D. How 17. ______ pen is this? Can I borrow it? * A. Whose B. whom C. who D. which Choose the letter A, B, C or D to indicate the word whose underlined part is pronounced differently from that of the rest in each of the following questions. QUESTION 18-19-20 18. "OU" * A. OUr B. cOUld C. wOUld D. shOUld 19. "I" * A. lIve B. hIgh C. fInd D. prIce 20. "O" * A. sOn B. Old C. cOld D. tOld nhanh giúp mình với có 15p thôi nhanh với đúng nhé mình càm ơn

Một ngôi nhà có khối lượng m = 150 tấn. Mặt đất ở nơi cất nhà chỉ chịu được áp suất tối đa là 10 N/cm2. Tính diện tích tối thiểu của móng.