Question - Subnetting

Consider the following scenarios -

A) You are an ISP that has been assigned a class B network with the address 145.34.0.0. You know you will service 200 to 250 small companies.

B) You are a medium-sized company assigned a class B network 156.26.0.0. You have seven divisions and want to assign each of them their own subnet.

C) You are a small company, of around 100 employees, assigned a class C network. You need to provide three LANs to each of the administration, marketing, and development departments.

For each of these cases answer the following questions:

How would you divide up your network to satisfy the requirements? Up to how many hosts can there be in each subnet? Show the slash notation for the subnets and the subnet mask. Is the subnet mask the same for each subnet? For a few of the subnets, show the network address and the broadcast address for the subnet. Are these resulting subnets class C networks?