We must protect our environment by following some preventive steps like 

1) Reduce plastic use 

2) Recycle correctly 

3) Use reusable bags specially cotton bags 

4) Support plastic free initiatives

5) Properly dispose plastic wastes. 
 
Classification of plastics 

1) PEt/PETE - Polythlene Terephthalate for example plastic bottles 

2) HDPE -High density polythlene for example milk jugs, detergent bottles 

3) PP- Polypropylene for example yogurt containers , bottle caps 

weight of plastics 

2 litres plastic bottle weight can be of approximate 50 to 70 grams

1 litres of milk jugs  weight can vary from 60 to 80 grams.
And weight of water bottle caps like small ones of soda or water bottle can weigh between 2 to 5 grams and 5 to 10 grams of medium water bottles and juice caps and 10 to 15 grams for large bottle caps . 

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