A1: Business Logic goes to Model part in MVC. Role of Model is to contain data and business logic. Controller on the other hand is responsible to receive user input and decide what to do.
A2: A Business Rule is part of Business Logic. They have a has a relationship. Business Logic has Business Rules.
Take a look at Wikipedia entry for MVC. Go to Overview where it mentions the flow of MVC pattern.
Also look at Wikipedia entry for Business Logic. It is mentioned that Business Logic is comprised of Business Rules and Workflow.
