Write the following in words rather than in figures or symbols.

1. 17.1% of adults have false teeth.
   Seventeen point one per cent of adults have false teeth.
2. According to a UN study, 2% of the world's population owns over 1/2 of all household wealth.
   
3. 0°C = 32°F
   
4. This article says that 8,556,981 people are currently living in London.