Key to Pre-unit Test 1 1
UNIT ONE 2
Lesson 1 Finding fossil man 2
Lesson 2 Spare that spider 7
Lesson 3 Matterhorn man 12
Lesson 4 Seeing hands 18
Lesson 5 Youth 23
Lesson 6 The sporting spirit 29
Lesson 7 Bats 34
Lesson 8 Trading standards 39
UNIT TWO 43
Lesson 9 Royal espionage 43
Lesson 10 Silicon Valley 48
Lesson 11 How to grow old 53
Lesson 12 Banks and their customers 57
Lesson 13 The search for oil 63
Lesson 14 The Butterfly Effect 68
Lesson 15 Secrecy in industry 73
Lesson 16 The modern city 78
UNIT THREE 83
Lesson 17 A man-made disease 83
Lesson 18 Porpoises 89
Lesson 19 The stuff of dreams 95
Lesson 20 Snake poison 100
Lesson 21 William S．Hart and the early‘Western’film 106
Lesson 22 Knowledge and progress 112
Lesson 23 Bird flight 118
Lesson 24 Beauty 124
Key to Pre-unit Test 2 129
UNIR FOUR 131
Lesson 25 Non-auditory effects of noise 131
Lesson 26 The past life of the earth 137
Lesson 27 The‘Vasa’ 142
Lesson 28 Patients and doctors 148
Lesson 29 The hovercraft 154
Lesson 30 Exploring the sea-floor 160
Lesson 31 The sculptor speaks 165
Lesson 32 Galileo reborn 170
UNIT FIVE 175
Lesson 33 Education 175
Lesson 34 Adolescence 181
Lesson 35 Space odyssey 187
Lesson 36 The Cost of government 193
Lesson 37 The process of ageing 198
Lesson 38 Water and the traveller 204
Lesson 39 What every writer wants 209
Lesson 40 Waves 215
UNIT SIX 220
Lesson 41 Training elephants 220
Lesson 42 Recording an earthquake 226
Lesson 43 Are there strangers in space? 231
Lesson 44 Patterns of culture 237
Lesson 45 Of men and galaxies 242
Lesson 46 Hobbies 247
Lesson 47 The great escape 252
Lesson 48 Planning a share portfolio 258