3. Scientists monitor the nitrate levels in a stream where the water shed is mature forest. They find an average of 2 mg/L of nitrate in the stream over a six-month period. Scientists cut down the trees in

the watershed and test the stream for nitrogen for the next six months. The average nitrate in the

stream rises to 18 mg/L.

Calculate the percent difference between the stream with the forest intact and the same stream

after the forest is removed.

Calculate the percent change in the nitrate level of the stream after the trees are removed.