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34－Adolescence
lijiao 486
33－Education
lijiao 233
32－Galileo Reborn
lijiao 236
31－The Sculptor Speaks
lijiao 256
30－Exploring the Sea-Floor
lijiao 314
29－The Hovercraft
lijiao 315
28－Patients and Doctors
lijiao 257
27－The vasa
lijiao 212
26－The Past Life of the Earth
lijiao 288
25－Non-Auditory Effects of Noise
lijiao 170
24－Beauty
lijiao 199
23－Bird Flight
lijiao 288
22－Knowledge and Progress
lijiao 168
21－William S. Hart and the Early Western Film
lijiao 241
20－Snake Poison
lijiao 166
19－The Stuff of Dreams
lijiao 370
18－Porpoises
lijiao 336
17－A Man-made Disease
lijiao 380
16－The Modern City
lijiao 199
15－Secrecy in Industry
lijiao 276