HOTSPOT
You have a DHCP server named Server1 that runs Windows Server 2012 R2.
On Server1, you run the commands as shown in the exhibit. (Click the Exhibit button.)
To answer, complete each statement according to the information presented in the exhibit. Each
correct selection is worth one point.
Answer: 
why 210??
Because there is a exclusion 192.168.15.21-30
at first range is 11-200, then it gets set to 11-230 and then exclusion is created 21-30
4th line in powershell, adress range gets reset. and 20 adresses are excluded!
10 address are excluded; from 21 to 30
why 192.168.15.250 and not 192.168.10.250?
I believe that this is because the computer in question connected to the 192.168.15.0 subnet. Even though the computer has a DHCP reservation in the 192.168.10.0 range, it can still communicate with the rest of the network as there is a router in place at 192.168.15.1. DNS queries would then go to 192.168.15.250 as defined on that line.
I’m not sure what the 172.16.1.250 address is that they specified for the ReservedIP, but seeing as it’s the only address that is set that way (and since it’s in a different IP range), this might be a placeholder.
Hopefully someone with a better understanding can help confirm or revise my statements above.
192.168.15.250 – The computer with the MAC address is trying to connect to the network 192.168.15:- which has the DNS server attached 192.168.15.250, which comes from the command Set-DhcpServerv4Optionvalue -DnsServer 192.168.15.250 -Router 192.168.15.1 -ScopeId 192.168.15.0. The reservation on the MAC address is for the 192.168.10 network.
210 – A little bit of simple math here to find out the number of available addresses. The server scope is adjusted so the range is from 11 to 230. Including the border numbers, that is 220 available addresses. The exclusion command then excludes the addresses 21 to 30, which is a total of 10 addresses (including the borders).
Thus, 220 – 10 = 210 available addresses.