In a study of the ejects of add rain on fish populations in Adirondack mountain lakes, samples of yellow perch, Perea flaveseens, were collected. Forty percent of the fish had gill filament deformities and 70% were Stunted. Twenty percent exhibited both abnormalities. Find the probability that a randomly sampled fish will be free of both symptoms. If a fish has a gill filament deformity, what is the probability it will be stunted? Are the two symptoms independent of each other? Explain.