Cho m g hỗn hợp gồm Fe, Al, Cu vào 1 bình kín có 1 mol O2. Nung nóng bình một thời gian cho đến khi ngừng phản ứng thì V khí O2 giảm 3.5%, thu được 2.12 g chất rắn. Tìm m ?

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II. Choose the correct answer for each of the gaps to complete the following text. Television first came some sixty years ago in the 1950s. Nowadays, it is one of the most (1)................ sources of entertainment for both the old and the young. Television brings (2)............. for children, world news, music and many other (3)............... . If someone likes sports, he can just choose the right sports, (4)...................... . It is not difficult for us to see why (5)................... is a TV set in almost every home today. 1. A.cheap B.expensive C.popular D.exciting 2. A.news B.cartoons C.sports D.plays 3. A.sets B.reports C.channels D.programmes 4. A.athletes B.channel C.time D.studio 5. A.it B.this C.that D.there III. Read the passage, and decide whether the sentences are true (T) or false (F). Television is an important invention of the 20 th century. It has been so popular that we can't imagine what life would be like if there were no television. Television is a major means of communication and entertainment. It brings pictures and sound from around the world into millions of homes. Through television, viewers can see and learn about people, places and things in distant lands. Television widens our knowledge by introducing new ideas which may lead us to new hobbies and recreations. In addition to the news, television provides us with a variety of programs that can satisfy every taste. Most people now seem to like spending their evenings watching television than to go out. 1. Television is an important means of communication. 2. Television provides us with a variety of programs. 3. Most people don't like watching TV in the evening. 4. Television can't satisfy all our tastes. 5. People can learn many things through TV.