Which three statements about subqueries are true? （） ["Asinglerowsubquerycanretrieveonlyonecolumnandonerow.","Asinglerowsubquerycanretrieveonlyonerowbutmanycolumns.","Amultiplerowsubquerycanretrievemultiplerowsandmultiplecolumns.","Amultiplerowsubquerycanbecomparedusingthe"；>；"；operator.","AsinglerowsubquerycanusetheINoperator.","Amultiplerowsubquerycanusethe"；="；operator."]
If the power is 0 dBm， what is the power in mW？（） [" 0 mW"," 1 mW"," 10 mW"," 1.5 mW"]
“不敷衍塞责，不宣传有害学生身心健康的思想”，这属于教师哪个方面的职业道德？
高压断路器的主要结构一般大体可分为（），（），灭弧部分和（）。
Which of the following files cannot be cataloged using the CATALOG command？（） ["Data files","Control files","Archived log files","Files storing RMAN script"]
水蚯蚓
