1) They covered 40% of the U.S.
2) Approx. 1% is left
3) True
4) Iowa has 30 million acres
5) False- over 100 plant species.
6) They can grow as tall as 10 feet
7) The roots extend 12 feet below
8) Approx. 60 million lived on the prairies
9) By 1886 fewer than 600 existed
10) They kept the prairies from becoming a forest