求计算机网络试题！！！！

这是一组CCNA的subnet的题目
1. What valid host range is the IP address 172.16.10.22 255.255.255.240 a part of?
A. 172.16.10.20 through 172.16.10.22
B. 172.16.10.1 through 172.16.10.255
C. 172.16.10.16 through 172.16.10.23
D. 172.16.10.17 through 172.16.10.31
E. 172.16.10.17 through 172.16.10.30

2. What is the broadcast address of the subnet address 172.16.8.159 255.255.255.192?
A. 172.16.255.255
B. 172.16.8.127
C. 172.16.8.191
D. 172.16.8.255

3. What is the broadcast address of the subnet address 192.168.10.33 255.255.255.248?
A. 192.168.10.40
B. 192.168.10.255
C. 192.168.255.255
D. 192.168.10.39

4. If you wanted to have 12 subnets with a Class C network ID, which subnet mask would you use?
A. 255.255.255.252
B. 255.255.255.248
C. 255.255.255.240
D. 255.255.255.255

5. If you need to have a Class B network address subnetted into exactly 510 subnets, what subnet
mask would you assign?
A. 255.255.255.252
B. 255.255.255.128
C. 255.255.255.0
D. 255.255.255.192

6. If you are using a Class C network ID with two subnets and need 31 hosts per network, which
of the following masks should you use?
A. 255.255.255.0
B. 255.255.255.192
C. 255.255.255.224
D. 255.255.255.248

7. How many subnets and hosts can you get from the network 192.168.254.0/26?
A. 4 networks with 64 hosts
B. 2 networks with 62 hosts
C. 254 networks with 254 hosts
D. 1 network with 254 hosts

8. You have the network 172.16.10.0/24. How many subnets and hosts are available?
A. 1 subnet with 10 hosts
B. 1 subnet with 254 hosts
C. 192 subnets with 10 hosts
D. 254 subnets with 254 hosts

9. What mask would you assign to the network ID of 172.16.0.0 if you needed about 100 subnets
with about 500 hosts each?
A. 255.255.255.0
B. 255.255.254.0
C. 255.255.252.0
D. 255.255.0.0

11You have a Class C 192.168.10.0/28 network. How many usable subnets and hosts do you have?
A. 16 subnets, 16 hosts
B. 14 subnets, 14 hosts
C. 30 subnets, 6 hosts
D. 62 subnets, 2 hosts

13. You have the network 192.168.10.0/24. How many subnets and hosts are available?
A. 1 subnet with 10 hosts
B. 1 subnet with 254 hosts
C. 192 subnets with 10 hosts
D. 254 subnets with 254 hosts

14. You have a 255.255.255.240 mask. Which two of the following are valid host IDs?
A. 192.168.10.210
B. 192.168.10.32
C. 192.168.10.94
D. 192.168.10.112
E. 192.168.10.127

15. You have a Class B network ID and need about 450 IP addresses per subnet. What is the best
mask for this network?
A. 255.255.240.0
B. 255.255.248.0
C. 255.255.254.0
D. 255.255.255.0