简述脊索动物门的基本特征及分类有哪些？
In one of your online transaction processing （OLTP） applications， users are manipulating and querying a database table simultaneously. From the Segment Advisor， you find that one of the tables is highly fragmented and you want to shrink the table immediately without affecting the currently active queries. Which option would you use with the ALTER TABLE command to achieve this objective？（） REBUILD。 CASCADE。 TRUNCATE。 ROW MOVEMENT。 SHRINK SPACE COMPACT。 SHRINK SPACE CASCADE。
在开展新型农村社会养老保险试点的地区，所有农村居民不必缴费，到达符合领取养老金的年龄时可以直接领取新农保养老金。
Given： Which two statements are true about the result if the default locale is Locale.US？（） The value of b is 2.。 The value of a is 3.14.。 The value of b is 2.00.。 The value of a is 3.141.。 The value of a is 3.1415.。 The value of a is 3.1416.。
轴的结构及尺寸初步确定之后，还须校核轴的强度。
对于几级以上的肌力患者即可进行抗阻练习：（）
