How to answers above problems with details explanation based on network & data communications?

1. How many subnets and hosts per subnet can you get from the network 172.19.0.0255.255.240.0 ? 2. What is the last valid host on the subnetwork 172.27.230.0/23? 3. What is the broadcast address of the network 10.151.48.0/20? 4. What is the last valid host on the subnetwork 192.168.69.32/27? 5. How many subnets and hosts per subnet can you get from the network 172.17.0.0/22? 6. What is the broadcast address of the network 192.168.238.248/29? 7. What is the broadcast address of the network 192.168.222.192/26? 8. What is the last valid host on the subnetwork 192.168.195.64 255.255.255.192? 9. What is the first valid host on the subnetwork that the node 172.19.147.117 255.255.254.0 belongs to? 10. What is the broadcast address of the network 172.29.228.128 255.255.255.128