For a person learning to type, the number N of words per minute that the person could type after t hours of practice was given by the limited growth function below. What is the rate of improvement after 15 hours of practice? After 44 hours of practice? N = 101(1-e0.04) What is the rate of improvement after 15 hours of practice? words per minute per hour of practice (Round to the nearest hundredth as needed.)