The Earth's Moon is about 4.35 billion years, which means it existed when the solar system first existed. Hope this helps!
https://study.com/academy/lesson/how-geography-isolated-ancient-china.html
That video will explain everything. I have already learned this in school, and it is very important on the test. VERY IMPORTANT.
To calculate the slope, the formula is (y1-y2)/(x1-x2) , which in this case, the answer would be:

Hope it helps!
Answer:
The tempature would decrease
Explanation:
This is because the reflection would reflect the suns rays into spase and therefore cool the planet