Answer: scientific theory is an explanation of observations or events that is based on knowledge gained from many observations or events.
Answer:
Cells produce CO2 and use O2 thats why there is less oxygen in exhaled air bc cells used some and more CO2 bc body gets rid off extra CO2 like that
Explanation:
I hope I did't over complicate
Answer:
P waves are compressional which means they move through a solid or liquid by pushing or pulling similar to the way the sound travels through air, the particles of the material a P wave pushes through moves in the direction of the P waves energy, this is called the direction of wave propagation
Answer:
Doppler Red-Shift Evidence
Explanation:
The Doppler red-shift of light observed from distant stars and galaxies gives evidence that the universe is expanding (moving away from a central point). This allows for Big Bang Theory, because after a “bang” occurs all of the matter moves away from the point of origin.