The mean endurance time for a sample of 36 girls 4-5 years old was 9.5 minutes with a standard deviation of 1.86 minutes. If we assume that these are the true population mean and standard deviation, and if we also assume that the endurance time follows a normal distribution, what is the probability of observing 4 year old girl with an endurance of 7 minutes? Is the data set normally distributed? Explain your answer.