What does the photograph of the anaerobic digester silos and its caption help the reader understand

Each main point should be noted in an outline as a roman numeral o a capital letter a number 1 any of the above none of the above

Compare: what are the similarities and differences between "artificial flavors" and "natural flavors"? why does schlosser explain these two terms in such detail?

Describe how the festival of spring bring out the latent joy in human nature?