* $C_4H_9Cl$:
$CH_3-CH_2-CH_2-CH_2Cl$
$CH_3-CHCl-CH_2-CH_3$
$CH_3-CH(CH_3)-CH_2Cl$
$(CH_3)_3-CCl$
* $C_3H_6O$:
$CH_2=CH-CH_2-OH$
$CH_2=CH-O-CH_3$
$CH_3-CH_2-CHO$
$(CH_3)_2C=O$
* $C_2H_7N$:
$CH_3-CH_2-NH_2$
$CH_3-NH-CH_3$
Mng làm hộ mik 2 bài này với, mik cảm onnn ạ
Em không hiểu lắm ạ Cách xác định đường trung tuyến nằm trong tam giác kiểu gì ạ Giúp em với Xong em vote 5 sao và ctlhn ạ Em cảm ơn nhiều ạ Giúp em với
Tính nhẩm 49×5^2-70×5+25 Mình ko bt làm:<
Lm hộ mik 2 bài này với, mik cảm ơnn nhiều ạ
A.other B. leather C. weathy D. brother 2. A. television B. elephant C. section D. Swedish 3. A. explain B. current C. desire D. electric 4. A. threaten B. thread C. seat D. bread 5. A. deaf B. leaf C. meat D. heat Part II. Choose the word that has a different stress pattern from the others in the group. 1. A. affect B. polutte C. effect D. litter 2. A. cholera B. pollutant C. permanent D. groundwater 3. A. radiation B. political C. historical D. contaminant 4. A. seriously B. measurement C. scientific D. logical 5. A. aquatic B. historic C. physic D. bonical SECTION B. LEXICO AND GRAMMAR Part I. Choose the word, phrase or expression which best completes each sentence 1. It’s recommended that we become more concerned …… the environment around us. A. of B. to C. with D. about 2. Air ……., together littering, is cause many problems in our cities today. A. pollute B. pollution C. polluted D. polluting 3. On Christmas Eve, most big cities, especially London are .........with coloured lights across the streets and enormous Christmas trees. A. decorated B. hang C. put D. made 4. In the United, there are 50 …….and six different time zones across the country. A. states B. nations C. towns D. show 5. Nowadays you still see the ………men wear kits (skirts) to wedding or other formal occasions. A. Scot B. Scotland C. Scots D. Scottish. 6. What …… we do to prevent these natural disasters? A. may B. ought C. should D. be able 7. …….. at someone is usually considered rude. A. Point B. To point C. To pointing D. Pointing 8. My father shouted at me, …….. made me feel sorrowful. A. that B. who C. whose D. which 9. I believe that our new manager has the …… to work well in this business environment. A. inflexible B. flexibly C. flexibility D. flexible 10.“Are Mary and Peter still living in Paris?” - “No, they …….. to NewYork.” A. are just moved B.had just moved C. have just moved D.will just move 11. ‘What is the …….. of the USA ?’ – ‘The dollars.’ A. current B. population C. territory D. currency 12. We can see many international programs ……………...different channels. A.in B.at C. on D. of 13. This hat is different ..................... the one I had. A. for B. to C. from D. at 14. What will happen if the pollution .................. on.? A. puts B. goes C. keeps D. takes 15. He said he was afraid this article was .................. date. A. over B. on C. behind D. out of 16. I had to get up early, ...............I would miss the train. A. otherwise B. if not C. but D. unless 17. Most young people want to ........more about environmental problems. A.look after B.find out C.look for D.make out 18. ..................always gives me real pleasure. A. I arrange flowers B. The flowers are arranged C. Arranging flowers D. While arranging flowers. 19. Nga had difficulties in bringing the heavy box, and Mai, her friend, offered to help. Mai : “Need a hand with your heavy box, Nga ?” -Nga : “.....................” A. I don’t need B. Not at all C. That’s very kind of you D. No, thanks 20. Peter: “ ...............?” Mary: “ Well , I’dlike to see that dress” A. Do you want anything B. May I help you C. What would you like D. What do you want to do
Giups mik vs ak trl nhanh đúng vote 5*+ câu trl hay nhất
Tính giá trị của biểu thức sau:
Giúp mik nha mik sẽ đánh giá 5 sao
So sánh $\sqrt{48}$ và $\sqrt{17}$ $+$ $\sqrt{10}$
Vt calli câu seo "Cơm tró : (danh từ) Hai người nấu một đống người ăn. :) NL: :))))))))))))))))))))) Viết cóa tâm ko thì pay màu Tradi not digi
Loga.vn - Cộng Đồng Luyện Thi Trực Tuyến