Question

1. why do polymers allow the plastic bag to stretch and not leak when poked with a sharp pencil?

polymers are invisible
polymers are filled with air
polymers are long chains of molecules that can move and seal around the pencil
polymers are made of metal

Explanation:

Polymers are long - chain molecules. When a plastic bag made of polymers is poked with a sharp pencil, the long - chain polymer molecules can move and seal around the pencil, preventing leakage. Polymers are not invisible, not filled with air, and not made of metal.

Answer:

Polymers are long chains of molecules that can move and seal around the pencil.