plastic containers are used as storage devices because :
1. plastic containers are durable.
2.plastic containers are lite in weight so they are used as containers.
3.it does not react for many things
4. plastic is used because it is of low costs.
5.it can keep the items fresh.
no coal is not sonorous because when we beat it with any other material it does not produce sound so i conclude that it is not sonorous.
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