posted by jo .
The environmental protection agency (EPA) wanted to study the particular materials in the atmosphere in Bogus Basin at 7200 ft elevation. The sampled air rate was at 1.00 liter per minute and was allowed to run 24 hours per day for 30 days. At the end of the month the filter was weighed. the initial weight of filter paper was 87.8 and final weight was 130.8. What is the concentration in PPM based on milligrams per milliliter, what did the ppm concentration did they report?
...What ppm concentration did they report.
Have you thought that units may be necessary for the mass of the filter paper, both before and after the 30 day period?