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Các bn làm giúp mình với mình vote cho các bn làm giup mình 5 sao

1 a, x/20 = y/9 = z/6 và x - 20/y + 4 =13 b,x/3 = y/4 : y/5 = 2/7 và x - y - z = 46 c,x/2 = 2y/5 = 42/7 và 3x . 5y . 7z = 123 d,x/2 = 2y/3 =32/4 và x . y .z -108 2 a, a/4 = b/6 ; b/5 =c/8 và 5k -3b =-536 b, a/7 = b/6 ;b/5= c/8 và a -2b + c = 46 c, 5 . a =8.b = 3.c và a-2b =c = 24 d, a + 3/5 = b -2/3 = c - 1/7 và a+b+c =24 e,a/2 = b/3 = c/4 và a^2 + 3 . b^2 - 2 . c^2 = -16

e thay nick mới ạ vẽ đậu mầm zui

helo nhe minh can ai do giup ne ai bt giup nhe cho 5sao lien

đót cháy hoàn toàn 1 mol X cần 5,5 mol o2, thu được co2 và hơi nước có tổng số mol là 9. xác định ctpt của X biết X có PTK =90

đốt cháy hoàn toàn 9,2 g chất A(C,H,O) thu dược 8,96 lít co2(đktc) và 10,8 g h2o. tỉ khối hơi của A so với n2 =1,64. tìm ctpt của a

giúp mình gấp với ạ. cảm ơn mọi người

Exercise 5: Choose the best answer to complete each of the following sentences. 1. The accident was my fault, so I had to pay for the damage the other car. A. of B. for C. to D. on 2. I’ll be at home Friday morning. You can phone me then. A. on B. at C. in D. of 3. I’m going away the end of February. A. on B. at C. in D. of 4. When we were in France, we spent a few days Paris. A. on B. at C. in D. to 5. Our flat is the second floor of the building. A. on B. at C. in D. of 6. What time did they arrive the hotel? A. to B. at C. in D. on 7. I saw Tom a concert last Saturday. A. on B. at C. in D. for 8. John’s away at the moment. He’s holiday in France. A. on B. at C. in D. for 9. We travelled 7.30 train, which arrived at 10.00. A. in the B. on the C. by the D. by 10. Have you read any books Agatha Christie? A. of B. from C. by D. with Exercise 6: Choose the best answer to complete each of the following sentences. 1. “What time will you arrive?” “I don’t know. It depends the traffic.” A. of B. from C. for D. on 2. Thank you. It was very nice help me. A. of you to B. for you to C. for you for D. of you for 3. Why were you so unfriendly Linda? Have you had an argument with her? A. of B. to C. for D. with 4. I’m not very good repairing things. A. at B. for C. in D. about 5. "Who is Tom Wilso n?” “I’ve no idea. I’ve never heard A. about B. from C. after D. of him.” 6. It was a confusing situation. Many things were happening the same time. A. at B. on C. in D. of 7. I couldn’t decide whether to buy the sweater or not. , I decided not to. A. At the end B. In the end C. By the end D. For the end 8. The road is busy all the time, even . A. on night B. at the evening C. at night D. on the evening 9. We went the theatre last night. We had seats the front row. A. to - in B. for - on C. at - of D. in - at 10. “Where’s the light switch?” “It’s the wall the door.” A. in - on B. on - in C. on - by D. by - in

giải giúp ạ aaaaaaaaaaaaaaaaaaaa