What looks like a black hole, behaves like a black hole, but is bigger than a black hole? Two black holes! Astronomers last week discovered a pair of enormous black holes far out in the galaxy that appear to be dancing toward each other. However, astronomers say the collision is not likely to occur for several million years. Black holes are objects in outer space that are so dense that nothing can escape their gravity. They often sit in the center of a galaxy -- like the Milky Way --and suck up everything near them. The gravitational pull of a black hole is so intense that not even light (Which travels faster than anything else in space) can make it past without being swallowed. Black holes, like the one at the center of the Milky Way, are enormous. Scientists call some of them "supermassive", because they can be a few million times the size of most stars. Their size, their mass, and their inescapable gravity make black holes a giant force of nature in outer space. Because there is no light near black holes, astronomers cannot actually see them; they are completely invisible to us on the Earth. Scientists manage to detect the existence of a black hole by watching what happens to other objects, or matter floating in space. So how did scientists manage to get a good look at a region so faraway? The team used an orbiting NASA observatory known as Chandra. This special observatory uses X-rays rather than light to watch far out into space. Right before a star gets sucked into a black hole, it produces a large number of X-rays. Which of the following statements CANNOT be used to describe a black hole? A) It is an object in space that can be seen on the Earth. B) It has extremely strong gravity. C) It can suck up everything near them. D) It is an enormous object in the galaxy.
A
It's 10:30 pm, and 11-year-old Brandon Blanco is sound asleep at home. Suddenly, a loud noise wakes him up. Naturally, Brandon reaches for his cell phone. The message becomes clear: "R U awake?" Brandon' s use of technology doesn' t stop there. He also has a computer, a TV and three video-game consoles ( ) in his room. With so many choices, it' s no surprise that when he isn' t at school, he spends nearly every waking minute using one or more of these devices Brandon is hardly alone. According to a recent study by the Kaiser Family Foundation, kids aged 8 to18 are spending more time than ever before using electronic devices. How much time? More than seven and a half hours a day on average, the study found. The jump is the result of a huge explosion in mobile devices, says Victoria Rideout, the lead author of the study. Today, nearly seven out of ten kids have cell phones. Just five years ago, it was four out of ten. Often, kids multitask, or use more than one device at a time. " If you've got a chance to do something on your computer and take a phone call and have the TV on in the background, why not?" media expert Cheryl Olson says. Most experts agree technology has much to offer kids. But some worry the kids could be missing out on other activities like playing outside or hanging out with friends. " It' s a matter of balance," says Olson." You've got to work on it. " Multitasking while doing homework is another concern. Some kids listen to music, watch TV or use the phone while doing their homework. "It' s important to make sure that you can stop and concentrate on one thing deeply, " says Rideout. With new and exciting devices hitting stores every year, keeping technology use in check is more important than ever. " Kids should try," adds Rideout. " But parents might have to step in sometimes. " Which of the following is an example of multitasking according to the passage? A) Watching TV while using the computer. B) Talking on the phone while staying with others. C) Playing video games on the Internet. D) Listening to music while relaxing.
A
Q: When it comes to feeling better about yourself,nothing will help you like healthy eating.Controlling what you eat is a big factor in how you look and feel.If you think about it,so much of how we behave,how we feel,and how our bodies perform is based on what we put into them. The old saying "You Are What You Eat" is actually true.The problem is that a lot of mainstream diet books you might find in your local bookstore or online are trying to sell you diet plans that don't work and that might even make you sick. Healthy eating is great for your body.It doesn't take a rocket scientist to figure that out.Many people don't realize just how good healthy food is for them.By eating great foods that are natural and healthy,you can lose weight.You can also have a lot more energy.So you shouldn't just think of healthy eating as a way to burn fat,but you should also think of it as a way to get your life back in order. You can spend more time with your family and get more work done because you will have more energy.You will be impressed by how much better you'll feel by putting nutritious,natural foods into your body.Your look will be better.You'll have more energy,and you'll be happier. The important thing to remember when it comes to eating healthy is to not fall for any tricks.There are a lot of people out there looking to make quick money.They will tell you just something so they can sell a book or a video.What you need is to trust a diet plan that is right for your body.Educate yourself about your own body type.Find out what kinds of foods are best for you.If the diet book you trust doesn't teach you these important factors,then you might be reading bad information. According the passage, a good diet book should be one _ . A) that help you enjoy food B) that is popular among people C) that helps you choose suitable foods D) that supplies much information
A: C
Q: As I grew older, Dad was to build all sorts of things for me as I explored a variety of interests: magic tricks, a toy circus, neighborhood shows and science projects. From as early as I can remember to the time I left home for college, I continued to come to him with a design or an idea, and he would figure out how to build it. In fifth grade, a schoolmate and I wrote a puppet show that we wanted to perform for our class. I made the puppet heads myself, and I made the costumes and curtains with Mon---who was as expert designing and sewing with cloth as my father was designing and working with wood and metal. With Dad I made the puppet stage, in our own invented style between kid and adult with me saying something like, " It has to be this high, and it needs to come apart and fold up so it can fit in the backseat of the car, and it needs to set up fast, and it needs to have different color1ed lights on top with switches you can reach to control them and a curtain you can pull from under it, even if you still have a puppet on your hand." Dad figured out how to make it all work, making plans as we went along. Then with the tools in his shop he built it, and I helped. Dad also spent a lot of time out in the garage or in the driveway working on the family car. I don't remember that he ever took it to a professional auto-repair shop. Maybe to save money, but also because he could usually figure out what needed fixing, just by taking it apart and looking. Though not trained as an auto mechanic, he could look under the engine cover and take parts and pieces out, spread them on a tarp to catch the oil and figure out what was supposed to happen to the machine and then figure out what wasn't happening and then replace the worn-out part or whatever and then put everything back together again. The purpose of the writer's writing the passage is _ . A) to tell how his father made a puppet for him B) in memory of his parents C) to describe to the readers his memories about his father D) to argue that parents should help children to explore the world and make inventions
A: C