Question 1155414
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y = 4*e^(-0.5t) = 4*(e^(-0.5))^t.


e^(-0.5) = 2.71828^(-0.5) = 0.6065 = 1 - 0.3935.


Therefore,


y = 4*e^(-0.5t) = 4*(e^(-0.5))^t = 4*(1-0.3935)^t


is that presentation (that formula), you are looking for.
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Solved, explained, answered and completed.