1. Both Mercury and Mars have thin or little to no atmosphere compared to Earth. They also have very different surface temperatures. Explain why you think that is.

2. Explain the role gravity plays in the planet's orbit around the Sun.

3. Explain how the geocentric model compares to the heliocentric model.

4. Why would a scientific theory not be discarded completely when new evidence is discovered.

Must give a clear explanation and why, no copying/searching from different sites. Best answer I will make brainliest!