HW for week 4 & 5

Week 4: 2.9: 20, 25, 26, 37, 41
        3.1: 6, 8, 16, 17, 27, 44, 52, 53, 62
Due: Oct. 25

Week 5: 3.2: 3, 9, 15, 22, 25, 32, 34, 36, 39
        3.3: 7, 8, 9, 11, 29
        3.4: 4, 5, 11, 12, 16, 31, 35, 36, 40, 43, 46
Due: Nov. 1