把一个长方形分成6分，5份是不一定占这个长方形的56，因为没有说明是“平均分”；
故答案为：×．
Which of the following is not among the basic features of a relational database
A． It does not matter what order the rows are in.
B． It does not matter what order the columns are in.
C． Different columns should have different column names.
D． Different columns should have different data types.
根据流脑监测方案要求，发现流脑病例后城市必须在（）小时以内报告。
A、6小时
B、24小时
C、12小时
D、48小时
