IP address question?

[Kamate]

Xin chào tất cả,
Tôi mới đọc 1 cuốn sách về Networking trong đó có 1 câu hỏi ma tôi không biết đáp án, vì vậy tôi post lên đây mong mọi người giúp đỡ:

1>Hãy cho biết Mask của class-A ip address mà có thể có tối đa 164 subnets, mỗi subnet có tối đa 150 ip address ?

2>Each router has next hop information, which is typically refereed to as a “Forwarding Table”, or a “Forwarding Information Base”. The router forwards the packets based on the forwarding rules. Briefly describe the principle of Forwarding Rule and then by using that solve the following example.

Suppose a router has built up the routing table shown below. The router can deliver directly over interfaces 0 and 1, or it can forward packets to routers R2 and R3. Describe what the router does with a packet addressed to each of the following destination.
Subnet Address Subnet Mask Next Hop
128.96.39.0 255.255.255.128 Interface 0
128.96.39.128 255.255.255.128 Interface 1
128.96.40.0 255.255.255.128 R2
192.4.153.0 255.255.255.128 R3

Destination Addresses:
(a) 128.96.39.32
(b) 128.96.40.16
(c) 128.96.40.163
(d) 192.4.153.16

Mong các bạn hướng dẫn chi tiết (tôi la` 1 newbie)
Xin cám ợn