how to transfer data from one google account to another google account?

I have a few questions regarding transfer of android information and all data from one google account to another google account:

1. Is it possible to change my email address (gmail) for my google account? If this is not possible, can I create a new google account and transfer all information (google doc, calendar, email, etc) from the old account to the new one?

2. If I get a new android phone, how do I transfer all the data and record from my old phone to the new phone? Do I simply log in using my google account? Will my record in some game apps (like fifa 14 manager mode and ultimate team) be lost? Or will I be able to retrieve all my progress in the apps?

3. If I open a new google account (account B) and get a new phone, how do I transfer all the data in account A stored in my old phone to the new account B?

thanks