A. Application Programmers need to refer to domains in their Oracle Web`logic Server programming Interface
B. domains can be used to separate development， test， and production application， administration and operational responsibility， and organizational or business division 
C. one can share a configured resource or subsystem between domains
D. the concept of multiple domains is supported 

A. a server instance can be associated with multiple machines
B. a machine can be associated with multiple server instance 
C. a server instance can be associated with only a single machine 
D. a machine can be associated with only one server instance