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筒述库伦强度线与莫尔圆的关系。

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板块的边界并不都是海陆的边界，大部分板块既有陆地又有海洋。作为板块边界的活动构造带，有裂谷、俯冲带、碰撞带这三种类型。大洋中绵延数万千米的大洋中脊，中间就是裂谷。地幔物质从这里流出，形成新的洋底岩石，并把两边的板块不断推向两侧，裂谷是洋底的诞生地。某些陆上裂谷可能会产生新的海洋。与裂谷相反，位于大洋边缘的海沟是海洋板块的消亡带。洋底岩石圈在这里俯冲到大陆岩石圈之下，并潜入软流圈而消失。另外，如果边界两边都是陆地，这就形成碰撞带。随着碰撞角度的不同，这里或因挤压而隆起高山，或因剪切而形成断层，或者兼而有之。板块构造说是大陆漂移说和海底扩张说的合理引申。大陆的漂移是板块移动的表现之一。板块运动是地震、火山等事件及岛弧、陆缘山、海沟等地形特征的形成原因。大陆漂移是板块移动的表现之一，从全文看这句话是说（）

A. 板块移动是大陆漂移的动力
B. 板块移动表现为大陆漂移
C. 板块移动和大陆漂移的本质是相同的
D. 板块移动造成了大陆漂移

Text 2 A lot happens to your teeth. They are ground, braced, brushed, flossed, polished, drilled, filled, and if you do not take care of them, pulled. For your teeth, proper oral care is as essential as anything else you do for your body and your generally health. Fortunately, if there is any damage to your teeth modem dentistry techniques make it easier, faster and less painful to get the problem fixed. By definition, dentistry includes the study, diagnosis, treatment and the prevention of disease of the mouth, teeth, gum and jawbones. Today’s dentists use sophisticated equipment and pain- preventing medicines, but these have not always been around. The earliest historical records of dentistry are from Egypt from around 3600 BC. Aesculapius, a Greek physician who lived around 1250 BC, is credited with the idea of pulling disease teeth. Hippocrates, around 400 BC, wrote of applying ointments and using branding irons to treat disease of the mouth. Through the Middle Ages wealthy people were treated by physicians and surgeons, while poor people could look to the local barber to pull painful teeth. Modem dentistry emerged with the release of Pierre Fauchard’s book The Surgeon Dentist, A Treatise on Teeth. Fauchard is considered the father of modem dentistry. Later, the first school devoted to teaching dentistry opened in Baltimore in the USA in 1840. Green Vardiman Black invented a foot engine so dentists would have two free hands while using the dental drill. He also came up with the idea that gum disease was an infection caused by bacteria. This was later confirmed in 1960. An important contribution was made in 1944 when Dr. Horace Wells, a Connecticut dentist, first used nitrous oxide (laughing gas) as an oral anesthetic; today this method of administering anesthetic is employed for many dental and medical surgeries. The introduction of fluoride in toothpaste in the 1960s was a huge breakthrough; teenagers and adults today have a 50% better chance of not developing tooth decay. The 1990s saw a change in thinking when it came to fillings for cavities in teeth. Since the early 1800s silver amalgam--a combination of silver, tin and mercury--has been the standard filling compound. But modern fears about mercury poisoning have led many people to have their amalgam fillings replaced with plastic polymer fillings. Besides not having any mercury, plastic polymers have an advantage over metal fillings because the color can be matched to the surroundings tooth and the material can be chemically bonded to the tooth. Dentistry methods are sure to advance even more in the future. Things such as laser technology, which is used to eliminate diseased tissue or weld together damaged parts of teeth, will soon become a common practice in dentists’ offices. And computer-assisted technology is ushering in new advances in the area of tooth restoration. The primary goal of dentists is to develop early detection methods to prevent dental conditions from turning into dental problems. Caring for your teeth properly will lessen the number of visits you make to the dentist. Brushing properly, flossing every day, getting a professionally cleaning every six months and maintaining a diet low in sugar can aid in keeping your teeth healthy. Your teeth will stay in your’ mouth if you take care of them. Which one could be the best title of the article

A. Proper dental hygiene.
B. Major events in the history of dentistry.
C. Great people who have been dentists.
Dentistry methods.

Faces, like fingerprints, are unique. Did you ever wonder how it is possible for as to recognize people ______ Yet a very young child—or even an animal, such as a pigeon-can learn to recognize faces. We all take this ability for granted.A. Even a skilled writer probably could not describe all the features that make one face different from another.B. Like the human face, human personality is very complex.C. But we can easily tell the" good guys" from the" bad guys" because the two types differ in appearance as well as in actions.E. Bookworms, conservatives, military types-people are described with such terms.F. We also tell people apart by how they behav

某工程施工工期较长，能固结排水。当工程完工后，使用荷载短期内突增，宜选择的三轴压缩试验方式是______。