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Part 4 For this part, you will find it helpful to use a Venn diagram. You may submit a Venn diagram or thoroughly explain how you reached each answer. In a math 105 class of 30 students, a survey showed that 16 students used the ALEKS e-text at least once, 9 used a video at least once, and 4 used both the e-text and a video at least once. 1. How many students used only the e-text? 2. How many students used neither the e-text nor the videos at least once