4. Factories often release harmful substances into the atmosph substances pollute the air. An engineer wants to reduce air pollution
coming from a factory. First, she focuses on pollution from ash. She
places different materials over a model of a chimney to stop particles of
ash from getting into the air. She measures the amount of pollution that
each material catches and makes a graph of the results. *
28
24
20
16
Amount of Particles Removed (mg)
12
00
Material 1 Material 2 Material 3 Material 4
Material Designs
What should be the engineer's next step?
A Find and fix any problems with Material 4
R Make and sell Material 1 to nearby factories