Read the following article and select the best answer. Article: COLUMBUS, Ohio--The heart operation taking place in the pale-green operating room at the Ohio State University Medical Center was unusual. The patient, a 62-year-old man, was made to sleep, tied with blue drapes and lying face up on a narrow table. But no one was touching him. Instead, the operation was being performed by a robot, whose three metal arms went through pencil-sized holes in the man's chest. At the ends of the robot's arms were tiny metal fingers, with turning wrists, which held a tiny instrument, a light and a camera. The robot's arms and fingers were controlled by Dr. Randall K. Wolf, sitting at a computer in a corner of the operating room about 20 feet away. This sort of operation, heart surgeons say, is the start of what may be the biggest change in their profession since heart bypass surgery began nearly 30 years ago. "The reason we make cuts is that we have big hands," said Dr. Wolf, the director of the surgery at Ohio State. The robot's _ fingers, no longer than a nail on the small finger, at the end of the long sticks could work better. Eventually, surgeons believe, most heart surgery will be done by robots whose arms are put in through pencil-sized holes punched in patients' chests. Instead of directly staring into a patient's body, surgeons will view magnified images of the operation on computer screens. In theory, the doctor would not have to be in the same room, or even the same country, as the patient. Question: According to the passage, the reason that most operations require large cuts is that _ . - patients have large organs - surgeons have large hands - large cuts take less time - large cuts cost less money
surgeons have large hands

Read the following article and select the best answer. Article: ARE you a dog person or a cat person? With so many photos and videos of cats and dogs doing cute things online, it's easier than ever to answer which of these furry friends you like more. There are many reasons why people prefer one type of pet over the other. So, have you ever wondered what your preference for cats or dogs says about you? In fact, a 2010 study done by Sam Gosling , a psychologist at the University of Texas, US, and his graduate student Carson Sandy found that dog people are more extroverted agreeable and serious than cat people. "Cats will occasionally engage in social activities, but usually after only a few minutes they will abandon the game. Dogs, on the other hand, will often engage in play, like fetching a thrown lull, for hours at a lime," said Modem Dog magazine. Just on the basis of dogs' nature being more sociable than cats', you may expect that the personalities of dog people also reflect higher sociability. And Cosling's study found that dog people are generally about 15 percent more extroverted and 13 percent more agreeable, both of which are associated with social altitude. In addition, dog people are 11 percent more conscientious than cat people. "Conscientiousness" is a tendency In show self-discipline ,to complete tasks and aim for achievement. This quality also shows a preference for planned rather than spontaneous behavior. In comparison, cat people an; about 12 percent more anxious, but they are also 11 percent more "open" than dog people, due to a general appreciation for art, emotion, imagination, curiosity, adventure, unusual ideas and variety of experience. And people high on openness are more likely to hold unconventional beliefs. Despite vast differences, there an some things that cat people and dog people have in common. "Both types of people consider themselves close to nature, dislike animal-print clothing and generally optimists. " noted Mother Nature Network. Question: According to the article, both dog people and cat people _ . - are generally self-disciplined - are usually positive and care about nature - are likely to hold unconventional beliefs - like to wear animal-print clothing;
are usually positive and care about nature

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Read the following article and select the best answer. Article: The world's largest solar thermal plant is set to begin producing power in the United States by the end of the year. Wind and energy from the sun are generally considered clean, unlike energy from coal-burning power stations. However, environmentalists now worry that too much solar power development could harm the local environment. A California company -- BrightSource Energy is building a huge solar power plant in the Mojave desert, about 60 kilometers southwest of Las Vegas, Nevada. The plant is known as the Ivanpah Solar Electric Generating System. Joe Desmond works for the company. "This is actually one of the highest concentrations of sunlight in the world, out here in Ivanpah." explained Desmond. BrightSource Energy will deploy 170,000 specially designed mirrors to direct solar energy towards boilers on top of three power towers. The steam produced in the boilers will drive turbine to make electricity. Joe Desmond says the steam can reach temperatures of more than 260 degrees Celsius. "We can store the sun's thermal energy in the form of molten salt, so we can produce electricity even when the sun goes down. There is a lot of interest in concentrating solar power around the globe in environmnents where you have lots of sun, such as China, South Africa, the Middle East, North Africa, explained Desmond. Environmentalists generally support the idea of solar power, however, many are concerned about the effect of power plants on sensitive environment. Lisa Belenky is a lawyer with the Center for Biological Diversity, a private group. She says environmentalists are specifically worried about the effect of the Ivanpah Solar Project on the sensitive plant and animal life in that part of Mojave desert. "Even though the desert seems big, when you start cutting it up, it can really affect how the species and the animals and the plants are able to survive in the long run,"said Lisa Belenky. BrightSource Energy has already spent more than $ 50 million to move endangered desert tortoises away from the power plant.... Question: Why can the plant make electricity at night? - Because the sun's thermal energy can be stored in the form of steam. - Because the sun's thermal energy can be stored in the form of molten salt. - Because the sun'ss thermal energy can be stored through mirrors - Because the sun's thermal energy can be stored in the boilers.
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Because the sun's thermal energy can be stored in the form of molten salt.