Api Manager Questions

Hello,

Q1:

The api manager installs on port 9000.

Would I typically install the manager on port 80 for production use so my subscribers see a url like this?

http://api.mydomain.com/API/v1.0/ping?api_key=123456789abc

Q2:

If we are only going to have 1 API is there anyway to remove the /API from my example so it looks like this:

http://api.mydomain.com/v1.0/ping?api_key=123456789abc

Q3:

Since i am using the API manager would I put my actual API on an internal IP that only the API server has access to?

Q4: 

If am sending the api key to my api from the api manager, how does my api verify the api key is correct?  Do I need to connect to the redis db to check the api?