How+do+you+know+how+old+it+is?

How do you know how old it is?
 * To determain how old a star may be, youj have to find out the mass of the star first. Mass is the amount of matter in an object without the gravitational pull. To find out the mass of a sphere (sun) you need to apply 4/3*π*radius3. **
 * Therefore the sun's mass comes to a total of 1.98892*1,000,000,000,000,000,000,000,000,000,000 kilograms=1,988,920,000,000,000,000,000,000,000,000 kilograms approx. **
 * 1.98892*10^30 **