专利是无形财产权的一种，与有形财产相比，具有（）的特征。
A.独占性
B.时间性
C.地域性
D.合法性
参考答案：A, B, C
在TCP/IP参考模型中，应用层协议的______用来实现互联网中电子邮件传送功能。
A sum of $200,000 from a certain estate was divided among a spouse and three children. How much of the estate did the youngest child receive ？（）
(1)The spouse received of the sum from the estate, and tile oldest child received of the remainder.
(2)Each of the two younger children received $12.500 more than the oldest child and $62,500 less than the spouse.
A．条件(1)充分，但条件(2)不充分．
B．条件(2)充分，但条件(1)不充分．
C．条件(1)和(2)单独都不充分，但条件(1)和条件(2)联合起来充分．
D．条件(1)充分，条件(2)也充分．
E．条件(1)和条件(2)单独都不充分，条件(1)和条件(2)联合起来也不充分．
of the sum from the estate, and tile oldest child received of 
the remainder.