What is the role of the glass menagerie in the play? what are two things it represents? what does the glass unicorn symbolize?

The following are sumerian inventions, except

Because of the housing bubble, many houses are now selling for much less than their selling price just two to three years ago. there is evidence that homeowners with virtually identical houses tend to ask for more if they paid more for the house. what fallacy are they making?

What is the cause of their extinction