Question

Radium decays exponentially; it has a half-life of 1,600 years. Find a formula for the amount,...

Radium decays exponentially; it has a half-life of 1,600 years. Find a formula for the amount,

q(t),

remaining from 70 mg of pure radium after t years.

q(t) =

After how many years will there be 20 mg left? (Round your answer to the nearest year.)

yr

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