近年来,开放型试题已经成为推动同学们创造发展的热点。所谓开放型试题是指题目给定的条件不完备,解题的方法不固定,答案、结论不惟一的题目。1条件开放型试题此类试题给出的条件是不完备的、隐含的,或给出多余的干扰条件等。例1图1,A、B是一块厚度均匀的金属片上裁下的两小片,其中A是正方形的,B片的形状不规则,请你用三种方法较准确地测出B片的面积 In recent years, open-ended test questions have become a hot topic for students to create and develop. The so-called open-ended test questions refer to the incomplete conditions of the given topic, the unresolved method of solving the questions, and the answers and conclusions that are not the only ones. 1 Conditional open-ended questions The conditions given for such questions are incomplete, implicit, or give extra interference conditions. Example 1 In Fig. 1, A and B are two small pieces cut from a piece of metal with uniform thickness, where A is a square and the shape of B piece is irregular. Please use three methods to measure the area of ​​B piece more accurately.