题目

Are you sometimes stressed? Singing is a simple and effective way to reduce stress. It is beneficial mainly in the following three aspects.Physical Benefits【1】 This is especially recommended for the elders and those who have some form of disability in their voice. However, it is important to find a capable instructor to employ good singing techniques so as not to further damage vocal cords (声带) or lungs.Singing also helps to improve your posture (姿势). Most people think that singing begins and ends with their mouth. 【2】 Singing practice will get you used to the proper body posit已知集合A={x||2x-1|≤3}，B={x||x+2|＜1}，是否存在集合C同时满足以下三个条件：①C中含有3个元素；②C∩B≠∅；③C⊆[（A∪B）∩Z]．若存在，求出集合C；若不存在，说明理由．