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40－Waves
lijiao 495
39－What Every Writer Wants
lijiao 227
38－Water and the Traveller
lijiao 348
37－The Process of Ageing
lijiao 280
36－The Cost of Government
lijiao 375
35－Space Odyssey
lijiao 466
34－Adolescence
lijiao 316
33－Education
lijiao 322
32－Galileo Reborn
lijiao 299
31－The Sculptor Speaks
lijiao 344
30－Exploring the Sea-Floor
lijiao 396
29－The Hovercraft
lijiao 490
28－Patients and Doctors
lijiao 368
27－The vasa
lijiao 1362
26－The Past Life of the Earth
lijiao 174
25－Non-Auditory Effects of Noise
lijiao 313
24－Beauty
lijiao 218
23－Bird Flight
lijiao 273
22－Knowledge and Progress
lijiao 305
21－William S. Hart and the Early Western Film
lijiao 460