The junction __________ is used to explicitly denote that at least one of the elements together must participate in the relationship.

The relationship ______________ is the most important relationship between layers which shows how elements in one layer are served by the services of other layers (can serve elements in the same layer as well.)

The following example demonstrates that __________ relationships are used to model causal dependencies between two (sub-)processes and/or two events.

Complete the sentence. In the Business Layer metamodel, a Business Event accesses a _________ 

Relationship connectors can be used to connect different types of relationships.