4. Joseph was curious to determine if scent improves memory. A test was created where better memory is indicated by higher test scores. A controlled experiment was performed where one group was given the test on scented paper and the other group was given the test on unscented paper. The summary statistics from the experiment are given below. a. Calculate the difference in means in the experimental test grades (scented -unscented). A simulation was conducted in which the subjects' scores were rerandomized into two groups 1000 times. The dlfferences of the group means were calculated each tlme. The results are shown below. Simulated Group Difference of the Means b. Use the simulation results to determine the interval representing the middle 95% of the difference in means. to the nearest hundredth. c. Is the difference in means in Joseph's experiment statistically signicant based on the cimillatinn'? Fvnlain