giúp em cần gấp lắm ạ Cho hỗn hợp M gồm 2 axit cacboxylic đơn chức mạch hở X và Y(MX<MY) và ancol Z đơn chức ( Y và Z có cùng số nguyên tử hidro trong phân tử).Đốt cháy 0,5 mol hỗn hợp M cần 17,92 lit O2 (đktc) thu được 15,68 l CO2 và 16,2g H2O .Phần trăm khối lượng của Y là

cac ban oi giup minh voi minh can gap

Mọi người nhận xét hộ em ,pic của thằng bạn em chứ ko phải của em đâu nhé

Mọi người giúp mình nhé bài 1 bài 2 nhớ giải ra nha

a) 3 phần x-3 = 6 phần 9 b)[6 - 2x] = 4-3x

so sánh : $(-32)^{27}$ và $(-18)^{39}$

mọi người giải giùm em bài này với ạ em xin cảm ơn

BÀI TẬP INVERSION Ạ, LÀM HẾT GIÚP MK VỚI Ạ!! TASK 1. 1. He is so intelligent that he always scores high. ⇒ So…....... 2. He hardly bought an insurance when he had an accident. (1) ⇒ Hardly....... (2) ⇒ No sooner....... 3. The thief ran away. ⇒ Away....... 4. I could drive motorbike only when I reached 18. ⇒ Only when....... 5. He had hardly left the office when the telephone rang. ⇒ No sooner ....... 6. He is both intelligent and handsome. ⇒ Not only....... 7. She will never accept his proposal. ⇒ At no time....... 8. Mr. Bean rarely showed his intelligence. ⇒ Rarely....... 9. I phone him as soon as I went home. (1) ⇒ No sooner....... (2) ⇒ Scarcely....... 10. He only thought about having a holiday abroad after he retired. ⇒ Only after....... TASK 2. 1. He dived into the sea. ⇒ Into....... 2. He is such a lazy boy that no one likes him ⇒ Such....... 3. She is such a gentle girl that she speaks very softly. ⇒ Such....... 4. The girl lay on the bed. ⇒ On....... 5. It was not until she was 18 that she went abroad. ⇒ Not until....... 6. We can only improve our skills by training hard. ⇒ Only....... 7. We are here. ⇒ Here....... 8. He no longer drinks coffee. ⇒ No longer....... 9. He stood outside the door. ⇒ Outside....... 10. It was not until they were robbed of money that they became more careful. ⇒ Not until....... TASK 3. 1. He had hardly left the office when the telephone rang. ⇒ No sooner........ 2. I had only just put the phone down when the boss rang back. ⇒ Hardly........ 3. He didn’t finish his work until the bell rang. ⇒ Not until........ 4. We only began to see the symptoms of the disease after several months. ⇒ Only........ 5. A sleeping dog was lying under the table. ⇒ Under the table........ 6. His brother had rarely been more excited. ⇒ Rarely........ 7. The facts were not all made public until later. ⇒ Only........ 8. If I had realized what would happen, I wouldn’t have accepted the job. ⇒ Had........ TASK 4. 1. She had never been so happy before. ⇒ Never before....... 2. I have never heard such nonsense! ⇒ Never......... 3. I have never seen such a mess in my life. ⇒ Never in my life....... 4. Our profits have never been higher than they are this year. ⇒ Never....... 5. The film had never before laid on such a sumptuous celebration. ⇒ Never.......

Giúp mình với mình với :D Cho P = 2x^2 – 3xy + 4y^2 ; Q = 3x^2 + 4 xy - y^2 ; R = x^2 + 2xy + 3 y^2 . Tính: P – Q + R.

Mn giúp em với ạ!! Em xin cảm ơn