How to post cs response sheets?

In the instructions it is mentioned that the response sheets should be made into roll and then posted... 

1.Should I roll it and wrap it with that brown wrapper provided and just post it like that? Is it possible to post it that way? Or should I put the rolls in a envelope and then post it?

2. The brown wrappers have the Institiutes Noida address  printed on it...does that mean we cant submit it to the chennai or bangalore chapters?

Please Help. Thanks