龟兹，是佛教传入中国的第一站。宗教的传播，留下来的是文化和艺术的永恒。外来却扎根于中国文化的佛学，深深影响着中国文化和艺术的发展。在其沿丝绸之路向龟兹传播的过程中，汇聚了来自两河流域、南亚次大陆和地中海文明的多种文化和艺术风尚。同时，佛教的回传，又给龟兹注入了黄河长江文明下的汉地文化艺术传统。这种多元性的文化元素，日渐与当地的社会、经济、文化融合在一起，给龟兹画师们提供了丰富的养料、激发了创作灵感，通过融合发展，创造了瑰丽多姿的龟兹石窟艺术。

    石窟艺术中，建筑、雕塑和壁画三位一体。建筑提供了艺术开展的神圣空间，雕塑是灵魂和核心，壁画则是具体的阐释和展开。龟兹石窟壁画的艺术成就既基于深厚的本土文化底蕴，也源于对外来文化的兼收并蓄与融合，由此呈现出多元化特征。其题材和内容以本生故事、因缘故事和佛传故事等与释迦牟尼有关的故事画为主，佛教故事画内容之丰富，超过了印度和敦煌以及中原地区。其艺术风格分为龟兹风、汉风和回鹘风。其中，龟兹风融合了希腊化的犍陀罗艺术、印度本土风格的秣菟罗艺术和西亚波斯艺术元素，并创造使用了独特的菱格装饰构图形式和凹凸晕染法。凹凸晕染法凸显了人体的立体感，人物线条如“曲铁盘丝”。这种产生于西域的独特晕染法，后来被西域画家尉迟乙僧带到了长安，丰富了中国传统人物画的创作方法，在画史中被传为佳话。

    龟兹石窟中心柱窟的主室券顶中脊壁画，集中反映了中外文化的融合。在那里，常常有日天的形象——佛教中的天界诸神之一，掌管着太阳的运行。其艺术表现形式多样，既有源于自然的圆日造型，也有身披盔甲、坐于马车之上的王者造型。王者造型显然是受到古希腊神话中太阳神阿波罗形象的影响；而头戴虎皮帽的金刚形象更有古希腊大力神赫拉克勒斯的影子。在龟兹壁画中还出现有作为佛教护法神的双头金翅鸟形象，以及波斯萨珊王朝时期流行的联珠纹饰，这深刻地反映出西亚文化对龟兹艺术产生的重要影响。同时，中原地区汉代以来所流行的不同纹饰和汉地造像在龟兹石窟壁画中的出现，也明显地揭示出佛教艺术回传的历史轨迹。如同本生故事中的粟特商人形象呈现出中亚地区商业文明的印迹，身着各种服饰、形态多样的供养人绘画，也反映着多元文明在龟兹地区的和谐共存。

    跨民族、跨文化的包容性和多元性，成为龟兹石窟艺术的重要特征，既反映出龟兹文明的开放和文化自信，也见证了丝绸之路上文化的融通和共荣。沧海桑田，多元荟萃的龟兹石窟艺术在延续了五六百年之后，逐渐走向衰落。与此同时，地处河西走廊西端、西邻新疆东境的敦煌石窟艺术却是一派繁荣的景象。一枯一荣间，石窟艺术在龟兹与敦煌的互动传播中得到了更加辉煌的发展。

（选自徐永明、苗利辉的《从龟兹到敦煌》，有删节）

下列对汇率的理解正确的是(　　)

如图，在平面直角坐标系中，OABC是正方形，点A的坐标是（4，0），点P为边AB上一点，∠CPB=60°，沿CP折叠正方形，折叠后，点B落在平面内点B′处，则B′点的坐标为（　　）

    Herbal medicine (草药), which has been used for medicinal purposes, is the use of plants to treat diseases. Many herbalists use the entire plant, from the flowers, stems, leaves, and roots, in the form of everything from teas to pills. These plants contain natural, chemical things that can treat the body for a variety of diseases- such as allergies, asthma, rheumatoid arthritis, migraine, chronic fatigue, and cancer, among others.

    Nowadays an increasing number of people prefer to adopt these plants to treat their diseases because, compared with chemical medicine, herbal medicine has its own advantages. Herbal medicine and remedies (治疗) are more effective than chemical medicine for certain diseases. The chemical medicine given by a chemist could have certain negative side effects. However, many of the herbal medicine and remedies do not have negative side effects. If any, they are softer than chemical medicine. Obesity is the cause of many of the health problems. Herbal medicine can help weight-loss more effectively and improve overall health.

    However, the cure using herbal medicine and supplements (营养品) would take some time, and therefore people are supposed to possess enough patience. Worse still, herbal medicine contains a variety of ingredients (成分) and people have to be sure that their body agrees with the ingredients and that it is not allergic (过敏).

    A point worth mentioning here is herbal remedies and medicine for certain illnesses may have negative side effects. These side effects may not be shown at once, but would take months or even years. In the early stages, if the herbal medicine is not agreeing with you, it is wise to stop using it.

    When used correctly and directed by doctors, herbs can help treat a variety of diseases. But keep in mind that the herbal medicine industry is not regulated, so herbal products are often misleading and may contain additives (添加剂) and that are not listed on the label (标签). Some herbs may cause allergic reactions or interact with other drugs, and some are poisonous if used improperly or at high doses (剂量). Taking herbs on your own increases your risk.