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听力原文：Thank you for calling Blue Power. At the present time, we are experiencing electrical power outages in many residential neighborhoods on the north side of the city. It is believed that the stormy weather earlier this evening caused the power station on Lincoln Street to shut down. A crew is on its way to assess and fix the problem. We currently estimate that power on the city's north side will be back on by 8:00 p. m. If your power has not been restored by 10 p. m. , please call back to hear an updated status report. Thank you for your understanding.
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听力原文：W: Would you mind taking a look at my laptop when you get a chance？
M: I have a lot of work to do today. I can look at it tomorrow morning. What is the problem？
W: I can only have two programs open at one time. Then, if I open up a third, it freezes and I have to restart it. It' s really hard to get work done when it freezes up that much.
M: Okay. I think it' s a virus. I' II come to your office and check it at 9: 30 tomorrow. Before then, I want you to back up all of your important files.
What does the man want to know？
A．Research what television is best for him.B．Ask for a cheaper price on the television
Diamonds are just carbon in its most concentrated form, the element that makes up 18 percent of the weight of your body. There is no other gemstone as cherished as the diamond, but in truth, diamonds are no rarer than many other precious gems. They continue to demand higher market prices because the majority of the diamond market is controlled by a single entity.
The Origin of Diamonds
Carbon is one of the most common elements in the world, and is one of the four essentials for the existence of life. Humans are more than 18-percent carbon. When occurring in nature, carbon exists in three basic forms, of which diamond is an extremely hard, clear crystal.
Diamonds form. about 161 km below the Earth's surface, in the molten rock of the Earth's mantle, which provides the right amounts of pressure and heat to transform. carbon into a diamond. In order for a diamond to be created, carbon must be placed under at least 435,113 pounds per square inch (psi) of pressure at a temperature of at least 400 Celsius. If conditions drop below either of these two points, graphite will be created. At depths of 150 km or more, pressure builds to about 725,189 psi and heat can exceed 1,200 C.
Kimberlite Pipes
Most diamonds that we see today were formed millions (if not billions) of years ago. Powerful magma eruptions brought the diamonds to the surface, creating kimberlite pipes. Kimberlite is named after Kimberly, South Africa, where these pipes were first found. Most of these eruptions occurred between 1,100 million and 20 million years ago.
Kimberlite pipes are created as magma (岩浆) flows through deep fractures in the Earth. The magma inside the kimberlite pipes acts like an elevator, pushing the diamonds and other rocks and minerals through the mantle and crust in just a few hours. These eruptions were short, but many times more powerful than volcanic eruptions that happen today.
The magma eventually cooled inside these kimberlite pipes, leaving behind conical veins of kimberlite rock that contain diamonds. Kimberlite is a bluish rock that diamond miners look for when seeking out new diamond deposits. The surface area of diamond-bearing kimberlite pipes ranges from 2 to 146 hectares. Diamonds may also be found in river beds, which are called alluvial diamond sites. These are diamonds that originate in kimberlite pipes, but get moved by geological activity. Glaciers and water can also move diamonds thousands of miles from their original location.
Cutting Diamonds
There are special techniques that are used to cut and shape a diamond before it gets to the jewelry store. Diamond cutters first try to remove any impurities or irregularities in the diamond. Sometimes, diamonds have to be sawed with the use of a phosphor-bronze blade or laser. Then the diamond is rubbed by another diamond to create facets-tiny flat spots on the surface. Finally, the diamond is pressed against a rotating polishing wheel to give the diamond its finished look.
Rating Diamonds
Diamonds are judged on several factors that determine their beauty. Most diamonds never reach the consumer market because they are too flawed. Often, these diamonds are used for industrial purposes--as an abrasive, for drill bits or for cutting diamonds and other gems. If you've ever purchased a diamond, you've heard of the "4 Cs:"
1. Cut--This refers to how the diamond has been cut and its geometric proportions. When a diamond is cut, facets are created and the diamond's finished shape is determined.
2. Clarity
听力原文：W: You look really busy today. Are you going to have everything ready for tomorrow's workshop？
M: I've just finished arranging a screen and projector, and I still have to bring the chairs and desks into the conference room. I also have to make a dozen copies of handouts for the participants this afternoon.
W: Actually, I've just realized that there would be more people showing up. So I think you'd better double them.
M: No problem. I' II prepare them this afternoon.
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