Suppose that the owner of a fast food restaurant recently purchased a new soft drink machine, designed to dispense 16 oz for a small beverage. The actual amount dispensed is normally distributed and should have a mean of 16 oz, but the manager suspects that the machine may be underfilling the cups. He selects a random sample of 7 small soft drinks, as filled by the machine. The volumes dispensed into each cup, in ounces, are listed below. 15.7,15.8,15.6,16.1,16.0,15.7,15.5