The function of the noun phrase <em>green, leafy vegetables </em>in this sentence is that of the subject of the sentence.
What contains important vitamins for a healthy body? Green, leafy vegetables.
Just based off of my common knowledge of humor, I would say personally that "1. Is Rover really any brighter than a hamster, a chicken, or that kid who's always eating Play-Doh?
" supports the idea that the informational text uses a humorous tone.
A physical description of the character lets us know the character and the setting better.
Frank will need 400 fluid ounces 3 bottles is 384 he will need 4 bottles which is 512