Question

Please help!

The radioactive substance strontium-90 has a half-life of 28 years. In other words, it takes 28 years for half of a given quantity of strontium-90 to decay to a non-radioactive substance. The amount of radioactive strontium-90 still present after t years is modeled by the expression 80 * 2^-t/28 grams. Evaluate the expression for t = 0, t = 28 and t = 56. What does each value of the expression represent?

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Answer 1

80 * 2^0 = 80*1 = 80g amount initially
80 * 1/2 = 40 g amount remainign after one half life
80* (1/2)^2 = 80* 1/4 = 20 g amount remaining after 2 half lives

Answer 2

Thank you

Answer 3

welcome