图表示淀粉、脂肪和蛋白质在消化道各器官（依次用A、B、C、D、E表示）被消化的程度．

请回答问题：

（1）图中X在A处开始被消化，原因是A中具有可以消化X的消化酶______，在该酶的作用下，X被分解为______．

（2）三种物质均可在D处被消化，D器官与此功能相适应的特点是：______．

（3）胆汁也是一种消化液，与其它消化液相比不含______．那么，胆汁对脂肪的消化起什么作用呢？

请选用下面的材料进行探究．

材料：猪胆汁、花生油、清水、2支试管、滴管、量筒等．

①探究方案：______；

②预测现象：______；

③得出结论：______．

The United States counts its population every ten years, and each census reveals that the racial and ethnic mix is changing dramatically, so by the year 2050, the "average" American will not be descended from (1) , but the majority of U. S. residents will trace (2) ancestry to Africa, Asia, the Hispanic world, the Pacific Islands, or the Middle East. Once the United States was a microcosm of European nationalities, (3) the United States is a microcosm of the world. The United States is (4) considered a "melting pot" society by many of its residents. (5) , many people prefer the term "salad bowl." They use this (6) to describe American society. American society will soon be (7) nonwhite. "Melting pot" implies that the different ethnic groups blend together (8) one homogeneous (9) , "salad bowl" (10) that nationalities, like the ingredients in a mixed green salad, retain their cultural (11) . Earlier generations of (12) believed they had to learn English quickly not only to survive but also for (13) .
Now, many immigrant groups do not (14) the same need. Because there are many places in America (15) you can work, shop, get medical care, marry, divorce and die without knowing English. (16) , Chinatown in San Francisco and New York. Also, Los Angeles has many Vietnamese immigrants and immigrants from Mexico. (17) , many immigrant groups want their children to know their (18) culture. Many Hispanics, for instance, want their children to learn (19) English and Spanish and study the Spanish language in school. They are fighting for the (20) to bilingual education in many communities. In many communities they are in the majority.