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34－Adolescence
lijiao 474
33－Education
lijiao 219
32－Galileo Reborn
lijiao 223
31－The Sculptor Speaks
lijiao 244
30－Exploring the Sea-Floor
lijiao 302
29－The Hovercraft
lijiao 303
28－Patients and Doctors
lijiao 247
27－The vasa
lijiao 201
26－The Past Life of the Earth
lijiao 276
25－Non-Auditory Effects of Noise
lijiao 159
24－Beauty
lijiao 189
23－Bird Flight
lijiao 276
22－Knowledge and Progress
lijiao 157
21－William S. Hart and the Early Western Film
lijiao 229
20－Snake Poison
lijiao 156
19－The Stuff of Dreams
lijiao 359
18－Porpoises
lijiao 325
17－A Man-made Disease
lijiao 371
16－The Modern City
lijiao 188
15－Secrecy in Industry
lijiao 267