To apply function like:
§ Descendants MDX Descendants function
available as member function only you need to
§ … select with mouse desired member (one row) and right-click with mouse
§ … select Element functions menu
then select
§ … any Descendants from submenu

In our case let us try to see:
cities from
Dialog will appear:

§ to select desired Level select button Add

After selecting level:

§ select OK
After confirmation result is:
