Is the nitrate level high or low? what are the possible sources of nitrate upstream?

Explain why components that are naturally found in air can be considered air pollutants.

Which sequence of transformations on preimage ∆abc will not produce the image ∆a'b'c'? a. reflection across the line y = x b. rotation 180° clockwise about the origin followed by a reflection across the line y = -x c. reflection across the x-axis followed by a reflection across the y-axis d. reflection across the line y = -x followed by a rotation 180° counterclockwise about the origin e. reflection across the y-axis followed by a rotation 90° clockwise about the origin

What are seismic dampers and why are they important?