As with any exam, it will vary from person to person as to what is deemed to be difficult. Be sure you are familiar with each of the topics in the exam objectives listed below.
In project management, the resource breakdown structure (RBS) is a hierarchical list of resources related by function and resource type that is used to facilitate planning and controlling of project work. At a minimum, RBS includes the personnel resources, tools, machinery, equipment, fees and licenses needed for successful completion of a project. Money itself is not considered a resource in the RBS; only those resources that will cost money are included. The information in the RBS is organized in a fashion for easy recollection by all of those who may need it. All resources are broken down into categories as well as resource types that may be used for purposes of identifying needs in regards to human resources and staffing.