安全评价管理中,安全评价机构条件核查不包括()。
A.材料核查
B.现场核查
C.许可审查
D.会审
参考答案:C
-What are you doing for your vacation?
-I _______my little sister at home. My mother is very busy.[ ]
A. am look after
B. am looking for
C. am babysitting
D. am babysit
对长度为20的线性表进行冒泡排序,最坏情况下需要比较的次数为______。