Question

Sodium - 24 is a radioactive isotope of sodium that is used to study circulatory dysfunction. Assuming that 4 micrograms of sodium - 24 are injected into a person the amount A in micrograms remaining in that person after t hours is given by the equation A=4e^-0.046t.(a) Graph this equation(b) What amount of sodium - 24 remains after 9 hours. Round your answer to two decimal places.(c) What is the half life of sodium - 24. Round your answer to two decimal places.(d) In how many hours will the amount of sodium - 24 be 1 microgram. Round your answer to two decimal places.

Answer 1

The amount A in micrograms remaining in that person after t hours is given by the equation:

$A\left(t\right)=e^{-0.046t}$

The graph of the equation is given by:

When t = 9 the value of A is given by:

$A=e^{-0.046\times9}\approx0.66$

Therefore, the amount of sodium-24 remaining after 9 hours is approximately 0.66 micrograms

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