Yes, they are both post-70's episodes. #1 is Congressman Mackey to Oscar Finch in "Agenda for murder". #2 is the male killer to the female (played by Shera Danese) in "A trace of murder".
#4 is the guy from the Winston Insurance Company, in "Identity Crisis". #6 is a woman at the carnival that Columbo showed the picture of dead Geronimo to.