Why is coal considered to be a nonrenewable resource?
a. there is not very much of it in the ground.
b. it takes millions of years to replace.
c. it is very inexpensive.
d. it is very expensive to mine.

B

Explanation: National Geographic stated: “Non-renewable energy comes from sources that will run out or will not be replenished in our lifetimes—or even in many, many lifetimes” meaning that it’s a source or energy that will run out eventually due to the fact that it takes millions of years to make.

a polar bond is formed when electrons are shared unevenly between atoms

thats how its supposed to be