Why is the Earth separated into different layers? A. The different masses of each layer cause them to separate and layer. B. The different densities of each layer cause them to separate and layer. C. The different composition of each layer causes them to separate and layer.

D. The different volumes of each layer cause them to separate and layer.

What happens to the temperature within Earth as the pressure increases? A. The temperature remains the same.

B. The temperature decreases and then increases.

C. The temperature increases.

D. The temperature decreases.

Which of the following does not help scientists gather important information about the Earth and its layers?

A. Volcanic eruptions

B. Seismic waves

C. Earthquakes

D. Ocean currents

Which of the following is not a possible effectof increasimg carbon dioxide levels in the atmosphere ?

Drag each tile to the correct box. the body monitors the levels of oxygen in the blood to regulate breathing. isabel is running in a marathon and is near the finish line. she feels out of breath. how will her nervous system work to generate a reaction? arrange the tiles in chronological order. isabel's breathing rate increases. sensory receptors in the arteries detect low oxygen levels. the brain sends signals through motor neurons. sensory neurons generate an impulse. the central nervous system relays an impulse to certain brain regions.

20 point pls brianliest 1. what does a red shift mean? blue shift? 2. describe the big bang theory. according to this theory, how old is the universe? 3. scientists believe the universe is expanding. what is the evidence that supports this? 4. describe a nebula. 5. describe the 3 types of galaxies. what is a barred spiral galaxy? 6. what is a light year? how far is alpha centauri from earth? 7. describe the universal law of gravitation. be sure to include gravitational force between two objects. 8. describe the planets’ orbits around the sun. 9. what is the asteroid belt? where is it located? 10. describe rotation and revolution of earth. what determines an earth day and year? 11. how do galaxies exist? 12. compare and contrast the inner and outer planets. 13. what causes the seasons?