Phải giải thích rõ ràng nhaaa ! Cảm ơn mn nhìu ạ ! Read the following passage and mark the letter A, B, C or D to indicate the correct answer to each of the questions from 21 to 25. Old newspapers, magazines and other unwanted papers are collected by the rag-and-bone man. The recovered paper is then sorted according to the grade or type of paper before being sent to the recycling centre. There, the sorted papers are gathered and bundled into tight bales before they are transported to a paper manufacturing factory where they will be recycled into new paper. Only paper free of contaminants such as food, plastic, metal and other rubbish can be successfully recycled; otherwise, impurities and bacteria might be introduced into the recycling process and thereby affect the quality of the paper produced. At the paper mill, recovered paper is chopped up and mixed with water to form pulp slurry, which is then subjected to a series of washing where soap-like chemicals called surfactants remove ink from the paper. After the deinking process, the pulp slurry is sprayed onto a huge flat wire screen that is rapidly moving through the paper machine. Water drains out and fibres bond together into a web of paper which is pressed between rollers to squeeze out more water and smoothen the surface. Heated rollers dry the paper, which is then slit into smaller rolls or sheets and finally removed from the paper machine. Papermaking fibres can be typically recycled five to seven times before they become too short and are rejected by the paper machine. Recycling paper certainly benefits the environment because it requires at least 50 per cent less energy and up to 75 per cent less water than making paper from virgin fibres. Also, it reduces the demand for virgin fibre in the world. So, have you done your part to save Mother Earth? 21. What does "recovered paper" in paragraph 1 refer to? A. Old newspapers, magazines and other unwanted papers B. Paper transported to the paper mill C. Paper wrapped in tight bales D. Paper containing food, plastic, metal and other rubbish 22. According to paragraph 1,"bales"are ________. A. papers flattened by huge rollers B. papers pulped on a huge wire mesh C. papers stored in large containers D. large amounts of paper tied tightly together 23. What happens to papermaking fibers as a result of repeated recycling? A. It smoothens the fibers. B. It enables the fibers to bond together quickly. C. It dries up the fibers so that they can be cut into smaller sheets of paper. D. It shortens the fibers, thereby rendering them unfit for further recycling. 24. Recycling paper benefits the environment by ________. A. increasing the demand for wood B. encouraging the destruction of forests C. requiring not less than 50 per cent less energy D. needing about 25 per cent more water than virgin fibers 25. What impact does recycling paper have? A. It will result in a variety of vegetation. B. It will result in the destruction of fewer trees. C. It will result in the destruction of more trees. D. It will result in the creation of more rivers. Read the following passage and mark the letter A, B, Cor D to indicate the correct word or phrase that best fits each of the numbered blanks from 26 to 30. People’s lives will change dramatically in the next 50 years. We anticipate advances in genetics, medicine, and transportation, the opening of international markets, and more. People look enthusiastically (26) ________ the future. Yet, life today is also dramatically different from life 50 years ago, and that life was dramatically different from life 100 years ago. Is life "better" now than it was fifty years ago? For many people, (27) ________ answer is yes. But for many, the answer is no. Hunger, poverty, misery, and cruelty existed a hundred years ago. They existed thousands of years ago, and they exist today. "Technology" and "development" have (28) ________ life dramatically for great numbers of people. But to some people these benefits are not available, and their existence alone does not address the (29) ________ of those people. For all our "advancement", a large part of our world lives worse, or no better, than it did fifty years ago. A future in which all people could (30) ________ the fruits of this advancement would be a future truly worth celebrating. 26. A. to B. for C. at D. on 27. A. an B. a C. the D. Ø 28. A. progressed B. improved C. advanced D. changed 29. A. problems B. circumstances C. conditions D. troubles 30. A. benefit B. achieve C. include D. enjoy