Add and remove related elements in a model

Using the model diagram, you can add related elements in hierarchies of requirements or functional, system, and physical models. Relations can be created between two elements only if the relation type is valid for the element and the relation rules defined. For example, you may only add a functional block to another functional block; you cannot add a requirement to the functional block. However, if you are in a working context, you may add different types of elements to the working context, even though they may not be directly related to one another.