Unit One Big Bucks the Easy Way 1
Unit Two Deer and the Energy Cycle 30
Unit Three Why Do We Believe That the Earth Is Round? 52
Unit Four Jim Thorpe 73
Unit Six To Lie or Not to Lie The Doctor's Dilemma 103
Unit Seven The Luncheon 146
Unit Eight The New Caves 174
Unit Nine Journey West 202
Unit Ten Why People Work 227
Key To Text Learning 258
Index 266