Multicar accident often result in fatalities across the nation, records are kept of the total number of accident involving 10 or more vehicles. Over the past 25 years, the average number of accidents involving 10 or more cars is 7 per year. The standard deviation is 4, assume that the distribution is approximately normal and determined (a) the percentage of years accumulating fewer than 4 multicar accidents and (b) What is the percentage of years having more than 12 multicar accidents?