deletions | additions       diff --git a/section_begin_enumerate_item_item__.tex b/section_begin_enumerate_item_item__.tex  index 2ff05a8..619a03d 100644  --- a/section_begin_enumerate_item_item__.tex  +++ b/section_begin_enumerate_item_item__.tex 
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\begin{aligned}  \rho &= \rho(T,s) \\  \frac{dT}{dt} &= A^T_h \Delta_{h} T +   \frac{\partial}{\partial z} \left(A^T_z \frac{\partial T}{\partial z}\right) z}\right),  \\ \frac{ds}{dt} &= A^s_h \Delta_{h} T +   \frac{\partial}{\partial z} \left(A^s_z \frac{\partial T}{\partial z}\right) z}\right),  \\ \end{aligned}  \end{equation} где введён горизонтальный оператор Лапласа $\Delta_h \equiv (\nabla_h \cdot \nabla_h)