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40－Waves
lijiao 473
39－What Every Writer Wants
lijiao 209
38－Water and the Traveller
lijiao 330
37－The Process of Ageing
lijiao 261
36－The Cost of Government
lijiao 353
35－Space Odyssey
lijiao 447
34－Adolescence
lijiao 296
33－Education
lijiao 299
32－Galileo Reborn
lijiao 283
31－The Sculptor Speaks
lijiao 324
30－Exploring the Sea-Floor
lijiao 378
29－The Hovercraft
lijiao 472
28－Patients and Doctors
lijiao 351
27－The vasa
lijiao 1340
26－The Past Life of the Earth
lijiao 154
25－Non-Auditory Effects of Noise
lijiao 292
24－Beauty
lijiao 199
23－Bird Flight
lijiao 255
22－Knowledge and Progress
lijiao 285
21－William S. Hart and the Early Western Film
lijiao 438