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36－The Cost of Government
lijiao 397
35－Space Odyssey
lijiao 355
34－Adolescence
lijiao 515
33－Education
lijiao 260
32－Galileo Reborn
lijiao 260
31－The Sculptor Speaks
lijiao 284
30－Exploring the Sea-Floor
lijiao 341
29－The Hovercraft
lijiao 343
28－Patients and Doctors
lijiao 284
27－The vasa
lijiao 237
26－The Past Life of the Earth
lijiao 317
25－Non-Auditory Effects of Noise
lijiao 200
24－Beauty
lijiao 228
23－Bird Flight
lijiao 318
22－Knowledge and Progress
lijiao 197
21－William S. Hart and the Early Western Film
lijiao 269
20－Snake Poison
lijiao 193
19－The Stuff of Dreams
lijiao 396
18－Porpoises
lijiao 373
17－A Man-made Disease
lijiao 406