If a demand curve is unit elastic, then P times Q will remain constant when P changes.

A "decrease in demand" means that

A) the demand curve has shifted to the left. B) price has declined and consumers want to purchase more of the good. C) the demand curve has shifted to the right. D) the price of the good can be expected to decline, assuming supply stays constant.

Other things equal, if $100 billion of government purchases (G) is added to private spending (C + I g + X n ), GDP will:

A. increase by $100 billion. B. increase by less than $100 billion. C. increase by more than $100 billion. D. fall by $100 billion.