信息系统常见的危险有（）。
A、软硬件设计故障导致网络瘫痪
B、黑客入侵
C、敏感信息泄露
D、信息删除
E、电子邮件发送
参考答案：A, B, C, D
给句子重新排序，组成一段话。
A. First, we make a big ball of snow.
B. Can you make a snowman?
C. Put the small ball on the big ball.
D. Sure.
E. Then make another small snowball.
F. Carrot for his nose.
G. Let's make a face.
H. Some rocks for his mouth and eyes. Two sticks for his arms.
正确的顺序是: ____________________________________________________
根据《证券投资基金运作管理办法》及有关规定，债券基金应有（ ）以上的资产投资于债券。
A．30％
B．50％
C．60％
D．80％
