Answer and Explanation:
This question is about "Fast Food Nation"
The phrase that sets the tone for the laboratory's description is “Everywhere i looked, i saw famous, widely advertised products sitting on laboratory desks and tables. The beverage lab is full of brightly colored liquids in clearbottles. ”
By using these two phrases, the author shows an observant tone, which implies that even though the article itself has a sarcastic and accusatory stance, the author intended to observe, analyze and inform real and important things to readers.