A researcher wants to know the effect of lighting on snacking behavior. He knows that young adults normally eat an average of = 21 grams of light snack food each day. He selects a random sample of n = 100 adults and places them in a controlled room where lighting is manipulated to mimic mid-day sunlight. Bowls of crackers are made available. Snack consumption for the sample averages M = 18.7 and s = 9.1. Does lighting impact snacking behavior?