检验检疫单一般以净重填写，如写毛重或以毛作净必须注明。运输包装无标记填写：N/M或散装，裸装。( )
参考答案：对
23. The class is unusual_______ the students are all over fifty and none of them attended the middle school when they were young.
A．in how
B．in what
C．in which
D．in that
冒泡排序算法在最好的情况下的元素交换次数为______。
