An article reports that a sample of 220 juvenile rainbow trout fed a diet fortified with equal amounts of the amino acids taurine and methionine for a period of 70 days had a mean weight gain of 313% with a standard deviation of 25, while 220 fish fed with a control diet had a mean weight gain of 233% with a standard deviation of 19. Units are percent. Find a 99% confidence interval for the difference in weight gain on the two diets. (Round the final answers to two decimal places.)