Scientists have discovered a moon rock, and they determine that there is about 50%

4500 years old

Explanation:

Line up 50 to the graph on the y axis and it gives a x value of 4500

For Earth to make one complete revolution around the Sun takes 365.24 days. This amount of time is the definition of one year.

Effects of Revolution of the Earth: Certain areas are tipped towards, or away from, the sun at different times of the year. This tilting causes the four seasons of the year. The tilting also creates opposite seasons in the Northern and Southern Hemispheres.