零测度集 加送30分零测度集的定义 开区间可不可以改成闭区间 为啥可以或不可以 加送30分

可以改成闭区间.The kind of interval(open,closed,semiclosed ) is immaterial:in a covering by open intervals,including the endpoints does not change the lengths.区间的种类（开区间,闭区间,半开闭区间）是...