1)若要将一个B类的网络172.17.0.0划分为14个子网，请计算出每个子网的子网掩码，以及在每个子网中主机IP地址的范围是多少？
答：子网掩码是255.255.240.0
每个子网的网络地址：
172.17.16.0
172.17.32.0
172.17.48.0
172.17.64.0
172.17.80.0
172.17.96.0
172.17.112.0
172.17.128.0
172.17.144.0
172.17.160.0
172.17.176.0
172.17.192.0
172.17.208.0
172.17.224.0
每个子网主机IP的地址：
172.17.16.1~172.17.31.254
172.17.32.1~172.17.47.254
172.17.48.1~172.17.63.254
172.17.64.1~172.17.79.254
172.17.80.1~172.17.95.254
172.17.96.1~172.17.111.254
172.17.112.1~172.17.127.254
172.17.128.1~172.17.143.254
172.17.144.1~172.17.159.254
172.17.160.1~172.17.175.254
172.17.176.1~172.17.191.254
172.17.192.1~172.17.207.254
172.17.208.1~172.17.223.254
(2)将一个C类的网络192.168.25.0划分为6个子网，请计算出子网掩码、每个子网的网络地址，以及在每个子网中主机IP地址的范围，
子网划分知识
。答 :子网掩码:255.255.255.22
网络地址:
192.168.25.160
192.168.25.192
192.168.25.96
192.168.25.128
192.168.25.64
192.168.25.32
主机地址的范围:
192.168.25.161~192.168.25.190
192.168.25.193~192.168.25.222
192.168.25.97~192.168.25.126
192.168.25.129~192.168.25.158
192.168.25.65~192.168.25.94
192.168.25.33~192.168.25.62
(3) 若要将一个B类的网络172.17.0.0划分子网，其中包括3个能容纳16000台主机的子网，7个能容纳2000台主机的子网，8个能容纳254台主机的子网，请写出每个子网的子网掩码和主机IP地址的范围，
电脑资料
《子网划分知识》(https://www.unjs.com)。答：子网掩码分别是：255.255.192.0，255.255.224.0,255.255.255.0
网络地址 主机地址范围
172.17.0.0/18 172.17.0.1~172.17.63.254
172.17.64.0/18 172.17.64.1~172.17.127.254
172.17.128.0/18 172.17.128.1~172.17.191.254
172.17.192.0/18 172.17.192.1~172.17.199.254
172.17.192.0/21 172.17.192.1~172.17.199.254
172.17.200.0/21 172.17.200.1~172.17.207.254
172.17.208.0/21 172.17.208.1~172.17.215.254
172.17.216.0/21 172.17.216.1~172.17.223.254
172.17.224.0/21 172.17.224.1~172.17.231.254
172.17.232.0/21 172.17.232.1~172.17.239.254
172.17.240.0/21 172.17.240.1~172.17.247.254
172.17.248.0/21 172.17.248.1~172.17.248.254
172.17.248.0/24 172.17.248.1~172.17.248.254
172.17.249.0/24 172.17.249.1~172.17.249.254
172.17.250.0/24 172.17.250.1~172.17.250.254
172.17.251.0/24 172.17.251.1~172.17.251.254
172.17.252.0/24 172.17.252.1~172.17.252.254
172.17.253.0/24 172.17.253.1~172.17.253.254
172.17.254.0/24 172.17.254.1~172.17.254.254
172.17.255.0/24 172.17.255.1~172.17.255.254