Assume that a set of test scores is normally distributed with a mean of 120 and a standard deviation of 20. Use the 68-95-99.7 rule to find the following quantities. a. The percentage of scores less than 120 is% (Round to one decimal place as needed.) b. The percentage of scores greater than 140 is% (Round to one decimal place as needed. ) c. The percentage of scores between 80 and 140 is (Round to one decimal place as needed.)