(14 points) Fiber and breakfast cereal ~ In an attempt to learn whether cereals high in fiber are also high in sugar and calories, three researchers took a random sample of 22 brands of breakfast cereal and recorded the calories, sugar (in grams), and fiber (in grams) per serving for each brand. The researchers constructed a linear model using Fiber as the explanatory variable and Calories as the response variable to answer the question, "Can the amount of fiber per serving be used predict the amount of calories per serving in a given brand of cereal?"