các bạn chỉ cần viết đáp số thôi nhé(tớ đang cần gấp) thank you Bài 7: Ba đội công nhân được giao đắp một con đường. Nếu đội thứ nhất làm một mình thì sau 15 ngày sẽ hoàn thành công việc. Nếu đội thứ ba làm một mình thì chậm hơn đội thứ nhất 5 ngày nhưng nhanh hơn đội thứ hai 2 ngày. Hỏi nếu cả ba đội cùng làm thì sau bao lâu sẽ hoàn thành công việc? Bài 8: Ba vòi cùng chảy vào một bể nước. Nếu chỉ mở vòi thứ nhất thì sau 12 giờ sẽ đầy bể. Nếu chỉ mở vòi thứ hai thì sau 15 giờ sẽ đầy bể. Nếu đồng thời mở cả ba vòi thì sau 4 giờ sẽ đầy bể. Hỏi nếu chỉ mở vòi thứ ba thì sau bao lâu sẽ đầy bể?

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VI. Read the passage and fill a suitable word in each blank to complete its summary below. Nasreddin’s Visitors One day a visitor came to Nasreddin’s house. “I am your cousin from Konya,” he said, “and I have brought you a duck to celebrate the visit.” Nasreddin was delighted.He asked his wife to cook the duck, and served the visitor a fine dinner. The next day another visitor arrived. “I am the friend of the man who brought you the duck,” he said. Nasreddin invited him in and gave him a good meal. The next day another visitor arrived, and said he was the friend of the friend of the man who had brought the duck. Again Nasreddin invited him in for a meat. However, he was getting annoyed. Visitors seemed to be using his house as a restaurant. Then another visitor came, and said he was the friend of the friend of the friend of the man who had brought the duck. Nasreddin invited him to eat dinner with him. His wife brought some soup to the table and the visitor tasted it. “What kind of soup is this?'” asked the visitor. “It tastes just like warm water.” “Ah!” said Nasreddin, “That is the soup of the soup of the soup of the duck.” One day, Nasreddin had a ....................... (1) who claimed to be his ....................... (2) from Konya. The visitor brought a ....................... (3) as a gift, and Nasreddin’s ....................... (4) made some ....................... (5) with it, and served a fine meal. Then another visitor arrived, saying he was a ....................... (6) of the cousin;then a third, who said he was a friend of the friend of the cousin. They didn’t bring any ....................... (7), but Nasreddin gave them a meal anyway. However, when the ....................... (8)visitor arrived, Nasreddin became angry. Instead of soup, he served.................. (9) water. He told the friend of the friend of the friend of the cousin that it was soup of the soup of the soup of the .................... (10). (HELP ME!!!)