Câu 2: Cho R1=2 ôm ; R2 = 4 ôm,mắc nối tiếp vào hiệu điện thế U = 12 V. 1/ Tính điện trở tương đương của đoạn mạch. ​​ ​​​ 2/ Tính cường độ dòng điện chạy qua mỗi điện trở và hiệu điện thế giữa hai đầu mỗi điện trở 3/ Tính nhiệt lượng tỏa ra ở mỗi điện trở trong 1 phút theo đơn vị Jun và calo . 4/ Nếu mắc thêm điện trở R3 vào mạch điện trên thì điện trở tương đương của cả đoạn mạch lúc này là 3,6 W . Hỏi điện trở R3 được mắc như thế nào vào mạch điện trên ? Vẽ sơ đồ mạch điện trên. Tính điện trở R3

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Ai giỏi tiếng anh thì giúp mình với nhá III.​Choose the item among A, B, C or D that bets answers the question about the passage. ​Thanksgiving Day is a holiday that Americans celebrate the honor of everything the country offered to their ancestors, who were among the first immigrants to the United States. When they first came to America, they saw that there were enough food and opportunity for everyone. They were even helped by the Indians, who taught them how to grow all kinds of new vegetables, such as corn and yams, or sweet potatoes. ​On Thanksgiving Day, it is traditional to eat a big meal together. Americans eat food that was found here by their ancestors. They usually eat turkey with sweet potatoes, Indian corn bread, and have pumpkin pie for dessert. ​Every Thanksgiving Day, a giant parade is held by one of the most famous department stores in New York. It is an annual event. And at the end of the parade, children can even see Santa Claus, who is visiting from the North Pole. Santa Claus is invited to remind children and parents that Christmas is not far away. 26.​Thanksgiving Day is celebrated ​​. ​A. to honor the new country ​ B. to remind people of cold winter ​C. to honor their ancestors ​ D. to remind people of Indians 27.The first white people to America were helped by Indians ​​. ​A. to know how to grow new vegetables ​ B. to have more opportunities ​C. to form the new nation D. All are correct 28.The traditional meal on Thanksgiving Day is. ​A. a big meal with turkey, Indian corn bread, and pumpkin pie ​B. everything they have ​C. food provided by the Indians ​D. food provided by Santa Claus 29.What is the main activity in New York on Thanksgiving Day? ​A. A giant parade is held by one of the most famous department stores. ​B. A big march by Santa Claus. ​C. A giant parade is held by Santa Claus, children and their parents. ​D. A giant parade is held by the Indians.​​ 30.​Santa Claus is invited to the parade on Thanksgiving Day ​​. ​A. to remind everyone that New Year is not far away ​B. to remind everyone that a new Thanksgiving Day is coming ​C. to remind everyone that Christmas is not far away ​D. to remind everyone of their ancestors