Match each geographic region with its significant characteristic. acute water shortages
highest population density
one-fifth the size of the country
vast plains covered with grasslands
Geographic Region
Characteristic
Mid-Atlantic
Subarctic and Arctic
>
West
Midwest

This is all you, but i can give you some topics that you could try. if it rained when you want to do something outdoors, it 'limits' that human activity. maybe you want to do an experiment that goes throughout the whole year and you have to have above freezing the entire year. this 'limits' your activity. i thought of those just off of the top of my head. something that gets to me that might be getting to you is you are thinking too hard about what to do. think simply, and if it is too simple, then bump it up just a little bit.

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