Abstract:
For a considered class of completely decomposable torsion-free groups, comprising of itself all completely decomposable groups with final number homogeneous components, are found necessary and sufficient conditions, connected with types of component of the final rank, under which any fully inert subgroup commensurable with fully invariant. It is described of splitting mixed groups, in which any subgroup is projectively inert. It is shown that every projectively inert subgroups of the group form the sublattice in lattice of all its projectively inert subgroups.