1.如图1,甲、乙两个单位分别位于一条封闭式街道的两旁,现准备合作修建一座过街天桥.(1)天桥建在何处才能使由甲到乙的路线最短?注意:天桥必须与街道垂直.(2)天桥建在何处才能使甲、乙到天桥的距离相等?2.一块白色正方形布,边长是1.8米,上面横、竖各有两道黑条,如图2所示,黑条的宽是0.2米,怎样利用平移的知识,求出白色部分的面积? 1. As shown in Figure 1, Units A and B are located on both sides of an enclosed street and are now ready to work together to build a cross-over flyover. (1) Where is the flyover built to minimize the route from A to B. Note: Vertical with the street (2) Where is the flyover built to make A, B to the flyover distance equal? ​​A piece of white square cloth, side length is 1.8 meters above the horizontal and vertical have two black bars, as shown in Figure 2 As shown, the black bar width is 0.2 meters, how to use the knowledge of translation, find the white part of the area?