Get the coordinates of a face and a line

There is a face and a straight line, how can I use the selection method to get the coordinates of both.
If there is just one face or one line,I can achieve with the following code。

array = Sketchup.active_model.selection[0].vertices.collect{|v| v.position}

But if I select a face and a line at the same time, how do I get their coordinates?

model = Sketchup.active_model
ents  = model.selection.find_all {|e| e.respond_to?(:vertices) }
array =
points = {|subary| }

Thanks a lot!Mr.Dan

Or even shorter { |e| e.respond_to?(:vertices) }