Hint
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Remember that the time evolution of any variable \(x(t)\) governed by
a first-order system with a time-constant \(\tau\) for a time \(t) between an initial
value \(x(t_0)\) and a final value \(x(\infty)\) is the following:
<br/><br/>
\(x(t) = x(\infty) + (x(t_0) - x(\infty)) e^(-(t-t_0)/\tau)\)
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