风车应做成中心对称图形，并且不是轴对称图形，才能在风口处平稳旋转．现有一长条矩形硬纸板（其中心有一个小孔）和两张全等的矩形薄纸片，将纸片粘到硬纸板上，做成一个能绕着小孔平稳旋转的风车．正确的粘合方法是（　　）

判断 阅读下面的材料，判断下列句子是否符合短文内容。符合的涂T，不符合的涂F。（T="True," F = False)
   What is color? Why do some of the things around us look red, some green, others blue?
   Colors are really made by reflected(反射) light. We can see colors because most of the things reflect light. Something is red, for it reflects most of the red light. In the same way, if something is green, it reflects most of the green light. If something reflects all light, it is white. If it doesn't reflect any light, it is black.
   Some light is reflected. But the other light is taken in and turns into heat. The darker the color is, the less light is reflected, and the more light is taken in. For this reason, dark-colored clothes are warmer in the sun than light-colored clothes.