30. A researcher found that the average pace of a snail is 30 inches per hour, with a standard deviation of 2 inches per hour. Assuming the data is normally distributed fill in the blanks. a) 68% of the data is between and inches per hour. b) 95% of the data is between and inches per hour. c) 99.7% of the data is between and inches per hour. 31. A random sample of CO2 levels in a school has a sample mean of x=500 ppm and sample standard deviation of s=80ppm. Use the Empirical Rule to determine the approximate percentage of CO 2 levels that lie between 260 and 740ppm