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Người ta bơm nước vào một bể rỗng.Nếu chỉ vòi thứ nhất chảy thì sau 2 giờ sẽ đầy bể . Nếu chỉ vòi thứ hai chảy thì sau 3 giờ sẽ đầy . Nếu cả hai vòi chảy thì sau bao nhiêu giờ thì đầy bể. Giúp mình với mình đang cần gấp
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Task 1. Match the heading (A-E) to the paragraph (1-5) A. No computers for two days. B. Never again! C. Homework wasn’t as easy. D. I used my phone more. E. I didn’t want to listen to them talking! No computer day! How did you survive? 1._____Ben, Luton, UK It was very difficult. I had quite a lot of homework to do. Usually, I use the computer to find information and I write my essay on it. My dad has lots of books, atlases and reference books, but almost all of them are out of date. It wasn’t difficult to find information, but it took more time. 2.___Jenny, Des Moines, USA I didn’t have email contact with my friends. I hate it! I sent a lot of texts. A few of my friends also turned off their computers, but most of them didn’t. On Sunday, there were lots of emails to read. 3.____David, Los Angeles, USA I usually listen to sports on the Internet on Saturdays. I can listen to baseball from anywhere in the USA or football from Europe. I listened to my mum’s small kitchen radio. It was awful. There was no football at all. I won’t join in the next “no computer” day. 4.____Sara, Richmond, UK My main problem was music. The batteries in my MP3 player were flat. I don’t have a DVD player – only on my computer – so I listened to the radio. It wasn’t very good. A few DJs are OK, but most of them talk too much. 5.____Lisa, Swansea, Wales I read a lot. My mum has some good books. It was very relaxing. Usually my eyes hurt in the evening. Last Saturday, there were fine. I went to bed earlier, too. The next day, I didn’t turn on my computer at all. I wanted to finish my book.

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