A primary air pollutant is directly from the source and secondary pollutants are omitted from two or more different primary pollutants interact with each other in the atmosphere.
EX of primary: carbon monoxide, nitrogen oxide, sulfur oxid
EX of secondary: NO2 acid rain
When water is transferred from land to atmosphere by evaporation from the soil and by transpiration plants.
Answer: D. at most 10
Explanation:
Using the energy pyramid, the ratio of grassland to primary consumer to secondary consumer is: 100:10:1 respectively.
Thus if the grassland supports 100 cattle (primary consumer), the numbers of humans (secondary consumer) the cattle can feed will be;
100/10 = 10.