#2 Subnet 18.54.0.0/16 into 10 subnets
If you take 255-10 (255 being a full octave and ten being how many you need) you are left with 245. 245 in binary is displayed as 11110101. Since you can’t use this as a subnet mask you have to use the first 0 as your cut off. This would be 11110000 or 240. This will provide you with a range of 16 hosts or 0-15.
After subnetting the new subnet mask would be 255.255.255.240 or 11111111.11111111.11111111.11110000 this would allow for the 10 subnets (16 to be exact) this can be confirmed with the Octal set up for Binary: 1 | 1 | 1 | 1 | 0 | 0 | 0 | 0 | 128 | 64 | 32 | 16 | 8 | 4 | 2 | 1 |

Since the first address is the subnet’s network address then the first address network would be:
18.54.0.0
And since the last address is the subnet’s broadcast address then the first broadcast address would be:
18.54.0.15
The range of available IP addresses would be:
18.54.0.1 through 18.54.0.14
With this information I can now set up all the ranges for 16 separate subnets with the next being:
18.54.0.16 Network, 18.54.0.31 Broadcast, 18.54.0.17 through 18.54.0.30 Available IP address
18.54.0.32 Network, 18.54.0.47 Broadcast, 18.54.0.33 through 18.54.0.46 Available IP address
18.54.0.48 Network, 18.54.0.63 Broadcast, 18.54.0.49 through 18.54.0.62 Available IP