An English teacher is interested to know if the new learning program will help the grade 5 students to increase the number of correct remembered words. Thirty subjects learn a list of 30 words. Learning performance is measured using a recall test. After the first test all subjects are instructed how to use the learning program and then learn a second list of 30 words. Learning performance is again measured with the recall test. Based on the output of boxplot, it shows the there are no significant outliers in the differences between the two related groups. What type of statistical test should we use? Give a two-sentence explanation for your