I believe it is K or rather potassium
This uses the suns energy instead of using fossil fuels. For instance solar panel.
Answer :— Physical properties of plastic samples collected by SEA in the Atlantic Ocean indicate the collected material is made of HDPE (high density polyethylene), LDPE (low density polyethylene), and PP (polypropylene), which are used to make common household items such as milk jugs, plastic bags, and drinking straws.Plastics and polystyrene foam (Styrofoam) comprise 90% of all marine debris, with single-use food and beverage containers being one of the most common items found in ocean and coastal surveys.

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B! Is the answer welcome:))