HELP PLEASE


A snowstorm started at midnight. For the first 4 hours snowfall is at an average rate of 1/2 in per hour. For the next 6 hours the average rate was 1 inch per hour. It stoppped snowing for three hours then it started snowing again at an average of 1/2 inch per hour for the next four hours until the storm is over. Determine the average rate of change