\( C dT=\left(-A-BT+Q(t)c(T(t))\right)dt + \sigma dW(t) \)
where
\( Q(t) = Q_{\mathrm{base}} + X\sin{(t/\tau)} \), with \( Q_{\mathrm{base}} = 415.5 \), \( X = 2.0 \), and \( \tau = 5 \) years.
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