An Important characteristic that distinguishes perceptual regions from formal and functional regions is that perceptual regions are based on:

Ineed you to put up a picture of the map so i can you as much as possible.

The us is first  the  u.s. economy  remains the  largest in the world  in terms of nominal  gdp. however, the  u.s. economy  loses its spot as the number one  economy  to china when  measured  in terms of  gdp  based on ppp. in these terms, china's  gdp  is $23.19 trillion exceeds the  u.s. gdp  of $19.42 trillion

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Could  i have the map?