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Ask someone to teach the exercises of Chapter 9 of Mathematics in the seventh grade edition.
33. In a straight line? Take any point A, intercept AB = 16 cm, intercept AC = 40 cm, and find the distance from AB midpoint D to AC midpoint E.

34. Given the line segment AB, extend AB to C to make BC =? AB, if AB = 4 cm, find the length of AC.

35. The complementary angle of an angle is 150 15', which is more than four times that of this angle. Find the degree of this angle.

36. As shown in figure ∠AOB is the complementary angle of ∠BOC, OD is divided by ∠AOB, OE is divided by ∠BOC, and the degree of ∠DOE is obtained.