2-5的相反数为5-2，
绝对值是5-2．
故答案是：5-2和5-2．
It is said that he has and will arrive home in a few hours.
A．be set free
B．been set free
C．be set out
D．set off
下列在E-mail发送时用到的协议是（）。
A．SNMP
B．SMTP
C．POP3
D．TCP
