Bài 1 : Từ 1 tấn isopren có thể thu được bao nhiêu poliisopren? Bài 2 : Người ta sản xuất poliisopren từ 2- metylbutan. Nếu phản ứng điều chế isopren đạt 95% và phản ứng trùng hợp đạt 90% thì từ 7,2 tấn 2- metylbutan sẽ thu được bao nhiêu poliispren ?

Các bạn giups mình nhé ! Mình đang cần gấp . Mình cần chi tiết , đầy đủ . Cảm ơn các bạn rất nhiều !!!

Làm giúp mik phần 2 Luyện tập - Củng cố ạ

Cho 2 hàm số y= x (bình) (P) và y= -2x + 3 (d) a) Vẽ (P) trên mặt phẳng tọa độ. b) Tìm tọa độ giao điểm của (P) và (d) bằng phương pháp đại số. ( giúp em nha)

Mn làm xong rồi chụp hình gửi e với ạ

Cho ∆ABC có AB = 30cm, vẽ AH BC (H BC). AH = 24cm ; HC = 36cm. a) Tính độ dài cạnh BH, AC b) Chứng tỏ ∆ABC vuông

Mark the letter A, B, C or D to indicate the word that differs from the rest in the position of the main stress in each of the following questions. (0.25 mark/ correct answer) Câu 1 A. disease B. greenhouse C. balance D. climate Câu 2 A. infectious B. extinction C. energy D. emission Mark the letter A, B, C or D to indicate the word whose underlined part is pronounced differently from the other. (0.25 mark/ correct answer) Câu 3 A. carbon B. catastrophic C. academic D. absorb Câu 4 A. relic B. education C. excavation D. degree Mark the letter A, B, C, or D to indicate the sentence that is closest in meaning to each of the following questions. Câu 5 He stole all the money that was donated for his hometown’s charity. He was punished for that. A. He was punished for having stolen all the money that was donated for his hometown’s charity. B. He was punished on having stolen all the money that was donated for his hometown’s charity. C. He was punished for stole all the money that was donated for his hometown’s charity. D. He was punished for stealing all the money that was donated for his hometown’s charity. Câu 6 Having seen people suffer from poverty in Africa, he decided to stop wasting food and water. A. After he saw people suffer from poverty in Africa, he decided to stop wasting food and water. B. Since he didn’t want to suffer from poverty, he decided to stop wasting food and water. C. Because he has visited Africa, he decided to stop wasting food and water. D. After he saw people stop wasting food and water, he decided to visit Africa. Câu 7 Tourists should avoid buying things from people who sell foods on the street. A. Tourists should avoid buying things from people selling foods on the streets. B. Foods on the streets should be bought by tourists. C. Tourists should avoid buying things from people sold foods on the street. D. Tourists should avoid buying things from people is selling foods on the streets. Câu 8 Lan was the first student who submitted the assignment. A. Lan was the first student to submit the assignment. B. Lan was the first student to be submitted the assignment. C. Lan was the first student submitted the assignment. D. Lan was the first student submitting the assignment. Câu 9 The clothes that are being sold in the shop were imported from China. A. The clothes being sold in the shop were imported from China. B. The clothes being sell in the shop were imported from China. C. The clothes sell in the shop were imported from China. D. The clothes to be sold in the shop were imported from China. Câu 10 We visited an ancient house that was built a hundred years ago in Hoi An. A. We visited an ancient house built a hundred years ago in Hoi An. B. We visited an ancient house that built a hundred years ago in Hoi An. C. We visited an ancient house build a hundred years ago. D. We visited an ancient house being built a hundred years ago in Hoi An. Câu 11 The kids threw the empty bottles on the streets after the picnic. They were criticized for that. A. The kids were criticized for throw the empty bottles on the streets after the picnic. B. The kids were criticized for being throw the empty bottles on the streets after the picnic. C. The kids were criticized for having thrown the empty bottles on the streets after the picnic. D. The kids were criticized on throwing the empty bottles on the streets after the picnic. Câu 12 The structure that is being reconstructed is the main Citadel. A. The structure to be reconstructed is the main Citadel. B. The structure being reconstructing is the main Citadel. C. The structure being reconstructed is the main Citadel. D. The structure reconstruct is the main Citadel. Mark the letter A, B, C, or D to indicate the correct answer to each of the following questions. Câu 13 I _________ Hoi An ancient town many times but I’m still attracted to its beauty. A. have visited B. visited C. have been visited D. have been visiting Câu 14 A girl _________ Tracy came here to look for you when you were away to ask about the relic that you just found. A. named B. whose C. who name D. naming Câu 15 Before working at Facebook, she used to be an/a ________ at Google. A. internship B. major C. graduate D. intern

Các bạn ưi, 30' nữa là mik nộp rồi, giúp mik với, mik sẽ vote 5 sao nha. Bài 1: Viết biểu thức đại số: a. Tổng các lập phương của a và b b. Bình phương của tổng 3 số a,b,c c. Tích của tổng hai số x và 4 với hiệu hai số x và 4 d. Viết biểu thức tính diện tích hình thang có hai đáy a,b chiều cao h e. Viết biểu thức biểu diễn tổng các bình phương 2 số lẻ liên tiếp. f. Viết biểu thức biểu diễn tích 4 số nguyên liên tiếp. g. Tích hai số lẻ liên tiếp. h. Tổng hai số chẵn liên tiếp. Bài 2: Đọc các biểu thức sau: a. 7x2 b. (x+5)2 c. (x-4)(x+4)

Choose the best answer I war studying the kight went out(when/while) The boys were playing soccer the girls were skipping(when/while) My sister the chores now(is doing/war/doing) Tom handing in his notebooks on tome(is always forgetting/war always forgetting)

Câu 9.Cho các số không âm x,y,z thỏa mãn x+3z=8 và x+2y=9.Tìm giá trị lớn nhất của A=9.Tìm giá trị lớn nhất của A=x+y+z. Nhờ các bạn giúp mình nha^_^ mình cảm ơn!!!