Question

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?

Answer 1

isnt this just simple plug in? o.0

Answer 2

t=0=> 80
t=28=>40
t=56=>20
and these would each represent a cycle

Answer 3

or like when 1 half life occurred each time

Answer 4

cuz a half life period of time it takes for the amount of a substance undergoing decay to decrease by half and it decreases by half like observed above^^