Subnetting Problems

4. You are designing a subnet mask for the 172.23.0.0 network. You want 40 subnets with up to 600 hosts on each subnet. What subnet mask should you use?

5. What valid host range is the IP address 172.20.220.248/23 a part of?

6. Which subnet does host 172.25.45.240 255.255.255.0 belong to?

7. What is the first valid host on the subnetwork that the node 10.3.223.159 255.255.240.0 belongs to?