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40－Waves
lijiao 467
39－What Every Writer Wants
lijiao 205
38－Water and the Traveller
lijiao 326
37－The Process of Ageing
lijiao 258
36－The Cost of Government
lijiao 349
35－Space Odyssey
lijiao 444
34－Adolescence
lijiao 293
33－Education
lijiao 296
32－Galileo Reborn
lijiao 280
31－The Sculptor Speaks
lijiao 321
30－Exploring the Sea-Floor
lijiao 375
29－The Hovercraft
lijiao 469
28－Patients and Doctors
lijiao 348
27－The vasa
lijiao 1334
26－The Past Life of the Earth
lijiao 151
25－Non-Auditory Effects of Noise
lijiao 289
24－Beauty
lijiao 195
23－Bird Flight
lijiao 252
22－Knowledge and Progress
lijiao 282
21－William S. Hart and the Early Western Film
lijiao 435