在快手上进行批发生意，以下哪种做法最有利于吸引和保留客户？

一个空的ArrayList对象list执行以下操作序列：list.add("A"); list.add(0, "B"); list.add("C"); list.add(1, "D"); list.remove(2); 请问最终list中元素的顺序是怎样的？

A research study aims to investigate the impact of a new educational program on student performance. The study involves two groups of students: an experimental group that participates in the new program, and a control group that follows the traditional curriculum. If a pre-test is administered to both groups to establish a baseline for performance, what is the most important reason for random assignment of students to the two groups?

在数学中，函数f(x)在点x=a处连续的定义是什么？

下列哪项是神经语言程序学（NLP）的定义？