Across
- 1. The steel that reinforces our homes is acquired through _______
- 4. ______ is defined as the introduction of substances that do not normally belong in the environment.
- 7. Natural _______ need to be extracted and used to build housing.
- 8. Name of country that is 2nd largest producer of waste
- 9. Singapore's only landfill is called Pulau ________
Down
- 2. Cities sometimes burn their waste products through this
- 3. Cities sometimes build this to dispose of waste products
- 4. Air pollution can be tackled by encouraging ______ transport
- 5. During rain, __________ from agriculture are washed into water bodies.
- 6. In cities, human usually generate energy from the burning of ____ fuels