Question

I need an answer please!?

Answer 1

C. 4000 years

The half life of a substance is the time it takes for half of it to be destroyed( so half of it will be left)

so if we have 100g of a substance with half life of 2000 years

100g~~~>50g~~~>25g

It’ll take 2 periods of 2000 years=4000 years

Hope this helps:)