Use this information to answer questions 9 and 10.
The ozone is an important layer within the part of the atmosphere called the stratosphere.
It is very important in helping protect us and the Earth from the sun's ultraviolet rays. These rays are so bright and hot that they would dry up all the water on Earth. Without water all living things on Earth would die. The ozone layer also helps keep important gases, such as oxygen, within the Earth's atmosphere. Unfortunately, scientists have discovered that the ozone layer has become much thinner and often develops holes in certain areas. They think this is likely to be caused by particular chemicals that people use called CFCs (Chloro-Fluoro-Carbons). In the past these chemicals have been used in aerosol cans, fridges, fire extinguishers and air-conditioning machines. However, many countries have pledged to stop using CFCs in new products.
Why is the ozone layer so important?