In your own words explain how the process of radioactive decay is used to accurately date fossils

Radioactive elements or isotopes are atoms which release radiations over time and this cause decrease in their amount and convert to other isotope. This is also known as radioactive decay.

Half life: Half life of an radioactive element is the time, after which the amount of element remains half.

To accurately date fossils, we should know the half life of an element.

In radioactive decay one isotope change to other by emitting radiations with time. We check the amount of secondary isotope and then relate it to half life of element to know the time that how much time take to make this secondary element.

blue stars have the highest surface temp

stellar distances are usually expressed in light-years

the measure of a star's brightness is called magnitude

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