Which two statements are true regarding the default behavior of the ORDER BY clause? （） ["Null values are left out of the sort.","Character values are displayed from Z to A","Date values are displayed with the earliest value first.","Null values are displayed last for descending sequences.","Numeric values are displayed with the lowest values first."]
Which three features are supported in a license for Cisco Unified Contact Center Express Enhanced? （） ["database integration ","prompt and collect ","VoiceXML ","opening and parsing HTTP and XML documents ","PQ ","E-mail Queuing&e"]
电网中并联电容器的目的是（），改变电压质量和减少（）。
下列药物中，可用于治疗注意力缺陷及明显多动障碍的是（） ["利培酮","利他林","氟哌啶醇","安定","心得安"]
犯罪团伙的三个类型。
体位引流时病变部位（），以利于（）引流。
