Cho tam giác ABC vuông tại A, đường cao AH, AB=15cm, BH=9cm. A)Tính BC,AC,AH. B) gọi M là trung điểm BC. Tính diện tích tam giác AHM.

Giúp mình chỗ học tập từ tác giả với

I. Choose the best answer (A, B, C or D). 1. You need to be __________ to follow eggshell carving because it may take two weeks to complete one shell. A. fit B. patient C. careful D. interested 2. My sister is very keen on swimming, and she goes swimming three __________ a week. A. time B. a time C. times D. timings 3. If you choose sewing as your hobby, you will __________ you own clothes. A. make B. get C. do D. take 4. We often read the instructions carefully in order to make __________ of the things we like best. A. models B. copies C. uses D. meanings 5. What does your father do __________ his free time? A. in B. at C. while D. on 6. My brother doesn’t like ice-skating because he thinks it is __________ . A. dangerous B. danger C. in danger D. endangered 7. I think a hobby will always give you __________ and help you __________. A. pleased – relaxing C. pleasure – relaxed B. pleased – relax D. pleasure – relax 8. My sister’s hobby is sewing, and she can get the sewing patterns from the __________ magazines. A. fashion B. sports C. science D. cooking 9. You can share your stamps __________ other collectors __________ a stamp club. A. with – at B. with – in C. to – in D. to – at 10. If your hobby is greeting card making, you can give your __________to your friends as presents. A. money B. hobby C. products D. greetings 11. I think this hobby doesn’t cost you much, and __________ you need is time. A. all B. some C. all of D. most 12. My family enjoys __________ because we can sell vegetables and flowers __________ money. A. garden – to C. garden – of B. gardening – for D. gardening – with 13. Nowadays people __________ hours sitting in front of the computers. A. set B. spend C. take D. last 14. I think you should take up swimming __________ it is suitable for your health condition. A. because B. but C. although D. so 15. There are many __________ why it is important to have a hobby. A. facts B. details C. reasons D. answers 16. I join a photography club and all the members love reasons a lot of beautiful photos. A. make B. take C. making D. taking 17. Will you __________ making models in the future. A. find B. take up C. look for D. pick up 18. A hobby help you connect with __________ people. A. the other B. another C. other D. others 19. I love my sister’s paintings because she is very __________ in using colours. A. care B. careless C. creative D. imagine 20. Do you think that hobby is __________ and boring? A. danger B. easy C. interesting D. difficult

nhân ngày quốc tế thiếu nhi, một cửa hàng giảm giá 10% so với giá định bán nhưng vẫn lãi 12,5% so với vốn . Hỏi nếu không hạ giá thì cửa hàng lãi bao nhiêu % so với tiền vốn

Đun nóng 48,2 gam hỗn hợp X gồm KMnO4 và KClO3, sau một thời gian thu được 43,4 gam hỗn hợp chất rắn Y. Cho Y tác dụng hoàn toàn với dung dịch HCl đặc, sau phản ứng thu được 15,12 lít Cl2 (đktc) và dung dịch gồm MnCl2, KCl, HCl dư. Số mol HCl phản ứng là

giúp em với ạ chứ em đang bí 2 bài a và b

một lớp học có 42 hs .Số học sinh nữ chiếm 3/4 số học sinh nam . tính số học sinh nam của lớp đó.

Choose the best answer 1. There are many good programs ___________ teenagers A. on B. for C. to d. at 2. A person who watches TV is a(n) _____________ A. viewer B. newsreader C. weatherman D. MC 3. According to the TV__________, there is animal programme at 6 p.m today. A. remote B. sceen C. viewer D. schedule 4. _____________ I don't like this animal programme, I still try to watch it until the end. A. but B. So C. because D. although

`x/2`=`y/5` và x+y = -21 Làm ơn đừng spam

tính 1 cách hợp lý a,200-198+196-194+192-190+.....+8-6+4-2 b, 3 ²/8.11+3 ²/11.14+...+3 ²/2017.2020 c,1.2.3....9-1.2.3...8-1.2.3...7.8 ²