1. (1I points) The following data are scores of 11 students who participated in a psychology experiment . The scores represent the number of trials required to complete a memorization test . 12, 10 , 12, 11 , 8, 15, 14 , 17 , 9, 12,9 a. (3 pts ) Determine the mean , median , and mode . b. (4 pts ) Determine the range, interquartile, variance, and standard deviation. c. (4 pts ) Use appropriate statistics to summarize the data . Justify why do you use the statistics ? 2. ( 12 points ) One fitness test for high school boys is the mile run . The times for all high school boys are approximately normally distributed with mean 450 seconds (seven and a half minutes ) and standard deviation 40 seconds . Determine the following probabilities a. (8 pts ) A randomly sampled school boy will run the mile slower than 8.5 minutes. b. ($ pts ) A randomly sampled school boy will run the mile faster than 6.5 minutes c. (3 pts ) Four independently random sampled persons will all run between 5.5 and 9.5 minutes. d. (3 pis ) A physical-fitness association wants to designate the fastest 5% as "excellent". What time should the association set for this criteria