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40－Waves
lijiao 480
39－What Every Writer Wants
lijiao 217
38－Water and the Traveller
lijiao 338
37－The Process of Ageing
lijiao 271
36－The Cost of Government
lijiao 362
35－Space Odyssey
lijiao 455
34－Adolescence
lijiao 303
33－Education
lijiao 308
32－Galileo Reborn
lijiao 291
31－The Sculptor Speaks
lijiao 333
30－Exploring the Sea-Floor
lijiao 386
29－The Hovercraft
lijiao 480
28－Patients and Doctors
lijiao 360
27－The vasa
lijiao 1351
26－The Past Life of the Earth
lijiao 163
25－Non-Auditory Effects of Noise
lijiao 300
24－Beauty
lijiao 206
23－Bird Flight
lijiao 263
22－Knowledge and Progress
lijiao 293
21－William S. Hart and the Early Western Film
lijiao 447