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40－Waves
lijiao 477
39－What Every Writer Wants
lijiao 214
38－Water and the Traveller
lijiao 334
37－The Process of Ageing
lijiao 266
36－The Cost of Government
lijiao 358
35－Space Odyssey
lijiao 452
34－Adolescence
lijiao 300
33－Education
lijiao 304
32－Galileo Reborn
lijiao 288
31－The Sculptor Speaks
lijiao 329
30－Exploring the Sea-Floor
lijiao 383
29－The Hovercraft
lijiao 477
28－Patients and Doctors
lijiao 357
27－The vasa
lijiao 1346
26－The Past Life of the Earth
lijiao 159
25－Non-Auditory Effects of Noise
lijiao 297
24－Beauty
lijiao 203
23－Bird Flight
lijiao 260
22－Knowledge and Progress
lijiao 290
21－William S. Hart and the Early Western Film
lijiao 444