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Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 36 to 42. 

     Today we take electricity for granted and perhaps we do not realize just how useful this discovery has been. Steam was the first invention that replaced wind power. It was used to drive engines and was passed through pipes and radiators to warm rooms. Petrol mixed with air was the next invention that provided power. Exploded in a cylinder, it drove a motor engine. Beyond these simple and direct uses, those forms have not much adaptability. 

     On the other hand, we make use of electricity in thousands of ways. From the powerful voltages that drive our electric trains to the tiny current needed to work a simple calculator, and from the huge electric magnet in steel works that can lift 10 tons to the tiny electric magnet in a doorbell, all are powered by electricity. An electric current can be made with equal ease to heat a huge mass of molten metal in a furnace, or to boil a jug for a cup of coffee. 

     Other than atomic energy, which has not as yet been harnessed to the full, electricity is the greatest power in the world. It is flexible, and so adaptable for any task for which it is wanted. It travels so easily and with incredible speed along wires or conductors that it can be supplied instantly over vast distances. 

     To generate electricity, huge turbines or generators must be turned. In Australia they use coal or water to drive this machinery. When dams are built, falling water is used to drive the turbines without polluting the atmosphere with smoke from coal. Atomic power is used in several countries but there is always the fear of an accident. A tragedy once occurred at Chernobyl, in Ukraine, at an atomic power plant used to make electricity. The reactor leaked, which caused many deaths through radiation. 

     Now scientists are examining new ways of creating electricity without harmful effects to the environment. They may harness the tides as they flow in and out of bays. Most importantly, they hope to trap sunlight more efficiently. We do use solar heaters for swimming pools but as yet improvement in the capacity of the solar cells to create more current is necessary. When this happens, electric cars will be viable and the world will rid itself of the toxic gases given off by trucks and cars that burn fossil fuels. 

The best title for this passage could be ______. 

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 31 to 35. 

     It used to be that people would drink coffee or tea in the morning to pick them up and get them going for the day. Then cola drinks hit the market. With lots of caffeine and sugar, these beverages soon became the pick-me-up of choice for many adults and teenagers. Now drink companies are putting out so-called "energy drinks”. These beverages have the specific aim of giving tired consumers more energy. 

     One example of a popular energy drink is Red Bull. The company that puts out this beverage has stated in interviews that Red Bull is not a thirst quencher. Nor is it meant to be a fluid replacement drink for athletes.  Instead, the beverage is meant to revitalize a tired consumer's body and mind. In order to do this, the makers of Red Bull, and other energy drinks, typically add vitamins and certain chemicals to their beverages. The added chemicals are like chemicals that the body naturally produces for energy. The vitamins, chemicals, caffeine, and sugar found in these beverages all seem like a sure bet to give a person energy. 

          Health professionals are not so sure, though. For one thing, there is not enough evidence to show that all of the vitamins added to energy drinks actually raise a person's energy level. Another problem is that there are so many things in the beverages. Nobody knows for sure how all of the ingredients in energy drinks work together. Dr. Brent Bauer, one of the directors at the Mayo Clinic in the US, cautions people about believing all the claims energy drinks make. He says, “It is plausible if you put all these things together, you will get a good result." However, Dr. Bauer adds the mix of ingredients could also have a negative impact on the body. "We just don't know at this point,” he says. 

What is the passage mainly about? 

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct word or phrase that best fits each of the numbered blanks from 26 to 30.

"Parents today want their kids to spend time on things that can bring them success, but (26) _______ we've stopped doing one thing that's actually been a proven predictor of success – and that's household chores," says Richard Rende, a developmental psychologist in Paradise Valley, Ariz, (27) _______ co-author of the forthcoming book "Raising Can-Do Kids.” Decades of studies show the benefits of chores - academically, emotionally, and even professionally. Giving children household chores at an early age helps to build (28) _______ lasting sense of mastery, responsibility and self-reliance, according to a research by Marty Rossmann, professor emeritus at the University of Minnesota. In 2002, Dr. Rossmann analyzed data from a longitudinal study (29) _______ followed 84 children across four periods in their lives - in preschool, around ages 10 and 15, and in their mid-20s. She found that young adults who began chores at ages 3 and 4 were more likely to have good relationships with family and friends, to achieve academic and early career success and to be self-sufficient, as (30) _______ with those who didn't have chores or who started them as teens. Chores also teach children how to be empathetic and responsive to others' needs, notes psychologist Richard Weissbourd of the Harvard Graduate School of Education. 

but (26) _______ we've stopped doing one thing that's actually been a proven predictor of success