Read and listen to the article. Complete the article with numbers and measurements from exercise 2.
There are many amazing stories of human survival, but actually our bodies are very fragile and do not cope well with extremes. Polar explorers can cope with temperatures of 1________, but only if they keep warm. Most people will collapse if their body temperature drops by only 2________, and if it drops by 3________, they'll die. Heat can be just as dangerous. Temperatures of 35°C are safe, provided humidity is not above 4________. High altitudes are dangerous too. We pass out when the pressure falls below 5________ of normal atmospheric pressure. This happens at about 6________ metres. Climbers can go higher because their bodies gradually get used to it, but no one survives for long at 8,000 metres. At high altitudes, lack of oxygen is another problem. At ground level, about 7______ of the air is oxygen. If that falls below 8________ , we die.
1. 40°c
2. 5°c
3. 15°c
4. 50%
5. 57%
6. 4,500
7. 1/5
8. 1/10
