Nancy was contemplating the purchase of a new oven for her kitchen, but she could not decide between an electric or a gas unit. Thus, she decided to conduct an experiment using the ovens-one gas, one electric-of two friends who live in adjoining apartments. She mixed up two identical batches of brownies under identical conditions of relative humidity and identical altitudes, put them into identical baking dishes, and cooked them at the same temperature for exactly the same time. The brownies cooked in the electric oven came out moist, while the brownies cooked in the gas oven came out relatively dry. Nancy concluded that baking in the electric oven caused the brownies to be moist. Construct a table that supports this conclusion. Which one of Mill's methods did Nancy use? What sense of causality is involved in the conclusion?