B= 1/3x4-1/4x5-1/5x6-1/6x7-1/7x8-1/8x9-1/9x10 mai mk nộp rồi

quạo sấp mặt từ tối tới giờ ko canh đc câu nào cả mệt ==" vẽ meme 2 cái nha kiểu như mấy cái dưới meme vẽ

y : 0,25 + y : 0,125 - y : 1 = 12,4

Một dd (A) chứa H2so4 và HCl ở cùng nồng độ mol Cho hh (X) gồm Fe,Mg và Zn.Làm 2 thí nghiệm: TN1:Cho m gam X tác dụng với 300g dung dịch A thu được 8,96 lít H2 TN2:Cho m gam X tác dụng với 600ml dung dịch A thu được 11,2 lít H2 a)Chứng tỏ rằng thí nghiệm 1 axit hết và X chưa tan hết;còn trong thí nghiệm 2 axit dư và X tan hết.Khối lượng m của X dùng trong các thí nghiệm đó nằm giữa hai giới hạn nào? b)Cho m=23,4gam.Khối lượng muối nằm ở giới hạn nào?

Làm giúp em phần b bài này vs ạ

III.Rewrite these sentences 1.The last time my father was to Vung Tau was 2 years ago. ⇒My father 2.The last time Betty rode to work was a fortnight ago. ⇒Betty has 3.He hasn't played tennis since 1990. ⇒The last time 4.I haven't met her for 2 months. ⇒The last time 5.Tom began playing the piano 4 years ago. ⇒Tom has 6.I started cooking for the party 4 hours ago. ⇒Tom has 7.My father is reading a newspaper.He started 2 hours ago. ⇒My father 8.My sister began to study English a year ago. ⇒My sister 9.She started working as a secretary 2 years ago. ⇒She 10.How long have you studied English? ⇒When 11.When did you begin to do research on lung cancer? ⇒How long 12.My father hasn't driven a car before. ⇒This is the first time 13.I've never met such a famous singer before. ⇒It's the first time 14.She has never been to the ballet before. ⇒It's the first time 15.She hasn't drunk Coca Cola before. ⇒This is the first time

cần giúp ạ tìm x,y,z (x,y,z đều là số nguyên) 2 tam giác có liên quan nhau

Làm giúp em phần a bài này vs ạ

Làm hộ mình bài này với ạ . cảm ơn nhiều

3. Put the verbs in brackets in the correct forms. 1. He (have)........ dinner when his friend called. 2. Joan ( travel ).......... around the world. 3.We ( not begin) ........... to study for the test yet. 4.Don’t get on a bus while it (run)........ 5. I ( invite) ............ them to my birthday party yesterday , however, they ( not come ) ........... 6.Look! Somebody ( clean ) ........... the room. 7.My brother (begin) ......... looking for a job in January. 8. Timson (make) .......... 13 films and I think her latest is the best. 9.She (cook) ............. at the moment. That’s why she can’t answer the phone. 10. She doesn’t mind (go) ............. out in the evening. 11. I (not see) ............. him since we (leave) ................ school. 12.Football (be) ......... my favourite sport. I like (play) ............ it in my free time. 13. Jane (leave) .............. just a few minutes ago. 14. She (be).............. extremely quiet since her husband died.