B. is the answer.
C is not correct because the light is actually reflected off of an opaque object.
Answer:
The valves prevent the backward flow of blood. These valves are actual flaps that are located on each end of the two ventricles (lower chambers of the heart). They act as one-way inlets of blood on one side of a ventricle and one-way outlets of blood on the other side of a ventricle.
Explanation:
This is because Gravity exists everywhere in the universe.
<h3>What is Gravity?</h3>
This is the force of attraction which acts on all matters in the universe. Astronauts appear weightless while in orbiting the Earth because the space shuttle and the astronauts are in free fall around it.
They fall at the same rate as the space shuttle which is why the astronauts appear weightless.
Read more about Gravity here brainly.com/question/88039
It stays constant, because it's using that energy to change state
True. No matter can be created nor destroyed in pretty much every aspect of life, especially chemical reactions.
