ABSTRACT
In this chapter we test the abstract concepts developed in the preceding chap ters more concretely on what is surely the simplest kind of almost completely de composable group with arbitrary critical typeset, namely the groups obtained as extensions of a completely decomposable group by a finite cyclic group. Such groups are a traditional source of examples since they are tractable and yet rich and varied in their properties. We will be able to obtain extensive and precise information about these groups, and hopefully this knowledge can eventually be used to study more general classes of almost completely decomposable groups by a suitable in ductive process.
