Please show work

1. What is the last valid host on the subnetwork 172.31.0.0 255.255.248.0? 2. What valid host range is the IP address 172.20.225.109/24 a part of? 3. What valid host range is the IP address 192.168.57.149/28 a part of? 4. What is the broadcast address of the network 172.18.168.0 255.255.252.0? 5. What is the first valid host on the subnetwork that the node 172.23.242.21 255.255.248.0 belongs to