Because plate movements have raised ancient sea floors above sea level,
a. there is less coral than there used to be.
b. coral reefs are only found in the deep ocean.
c. limestone that began as coral reefs can be found on the continents.
d. all remains of ancient coral reefs have been lost.

materials water oxygen those are the things i can think of in this moment.

the most common energy conversion is from kinetic energy to potential energy, and then from potential energy to kinetic energy.

later on comes the heat energy, mechanical energy, and other energy conversions.

this energy conversion is so common that we can find it in our day to day lives as well.

- one of the most common energy conversions involves the changing of potential energy to kinetic energy or kinetic energy to potential energy

the correct answer is b

hydrogen is a compound or a single element and a element is a pure substence that cannot be separated into simpler subtances

clorine is a compound its a chemical substance that forms when two or more different elements combine

so both hydrogen and clorine are compounds