Question 1204505
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There's a typo.
The Q0^e-kt should be Q0*e^(-kt)


Compare f(t) = 11(0.957)^t with f(t) = Q0*e^(-kt) to find that Q0 = 11.


The e^(-kt) part is the same as (e^(-k))^t or (1/(e^k))^t


Set e^(-k) equal to 0.957 to determine k.
e^(-k) = 0.957
Ln( e^(-k) ) = Ln(0.957)
-k*Ln( e ) = Ln(0.957)
-k*1 = Ln(0.957)
-k = Ln(0.957)
k = -1*Ln(0.957)
k = 0.043952 approximately
k = 0.0440 when rounding to 4 significant digits.


Answer:
f(t) = 11*e^(-0.0440t)
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