Question
Describe two changes that are harmful. Explain why you consider them harmful? How can you prevent them?
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Answer
Harmful changes are,
- Rusting of iron: Rusting of iron is harmful because it slowly destroys iron articles and makes them useless. Since, iron is used in making large number of objects or articles such as bridges, grills, railings, gates and bodies of cars, buses, trucks and ships, etc. Rusting of iron causes a great loss over a period of time. Prevention Rusting can be prevented by oiling, greasing or painting. It can also be prevented by galvanisation.
- Decaying of fruits: Decaying of fruits causes health hazards. Due to decaying of fruits, there is a lot of monetary loss in food industry. Prevention Fruits can be preserved by keeping them at low temperature and by using some specific preservatives.
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