Một thửa ruộng hình thang có đáy lớn 120m, đáy bé bằng đáy lớn và hơn chiều cao 5m. Trung bình cứ 100m 2 thu hoạch được 64,5kg thóc. Hỏi trên cả thửa ruộng đó thu hoạch được bao nhiêu tạ thóc?

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Mình cần gấp cảm ơn nhiều Bài 13: Đặt câu hỏi cho các cụm từ được gạch chân dưới đây. ​1.​Minh usually takes exercises (after getting up.) ​ ​2.​I brush my teeth (twice a day.) ​ ​3.​Nga has an appointment (at 10.30 )this morning. ​ ​4.​They live (in the city center.) ​ ​5.​I like “Tom and Jerry” (because it’s very interesting.) ​ ​6.​She is (worried )about the next examination. ​ ​7.​(Music )makes people different from all other animals. ​ ​8.​They do their homework ( at )night. ​ ​9.​I like (the red blouse, not the blue one.) ​ ​10.​That is (an English book.) ​ ​11.​He studies piano (at the university.) ​ ​12.​My father is (a teacher.) ​ ​13.​My favorite musician is (Trinh Cong Son.) ​ ​14.​We take a holiday (once a year.) ​ ​15.​It takes (four hours )to get there. ​ ​16.​He earns (a hundred pounds) a week. ​ ​17.​This book is (30.000 dong.) 18.​The car is (expensive.) ​Bài 15: Sắp xếp các từ sau để tạo thành câu hoàn chỉnh. ​1.​accident / an / she’s / in / because / hospital / she / had. ​ ​2.​but / they / many / work / don’t / hours / they / have / money / much. ​ ​3.​asked / Paul / me / question, / a / replied / I / so. ​ ​4.​buy / I / peppers / potatoes. / and / tomatoes, ​ ​5.​them / apple / can / have / an / or/ a / . / She / have / both /. / She / mango / can’t / of ​ ​6.​can / piano /./ Karthik / play / but / he / play / the/ can’t / the/ violin ​ ​7.​hard-working / is / but / her / is / lazy / . / She / very / brother ​ ​8.​clever / is / and / beautiful / . / she ​ ​9.​shirt / can / the / blue / or / take / green / shirt/ . / You / the ​ ​10.​/ am / sister / tall / I / short / . / My / is / but ​ Bài 16: Đọc đoạn văn và trả lời câu hỏi. How can we keep our teeth healthy? ​Firstly, we ought to visit our dentist twice a year. He can fill the small holes in our teeth before they destroy the teeth. He can examine our teeth to check that they are growing in the right way. Unfortunately, many people wait until they have toothache before they see a dentist. ​Secondly, we should brush our teeth with a toothbrush and fluoride toothpaste at least twice a day – once after breakfast and once before we go to bed. We can also use wooden toothpicks to clean between our teeth after a meal. ​Thirdly, we should eat food that is good for our teeth and our body such as milk, cheese, fish, brown bread, potatoes, red rice, raw vegetables, and fresh fruit. Chocolate, sweets, biscuits and cakes are bad, especially when we eat them between meals. They are harmful because they stick to our teeth and cause decay. ​1.​How often should we visit our dentist a year? ​ ​2.​What should we brush our teeth with? ​ ​3.​What else we can use to clean between our teeth after a meal? ​ ​4.​What kinds of food are good for our teeth? ​ ​5.​What kinds of food are bad for our teeth? ​