Consider a long concrete dam \((k=0.6 \mathrm{~W} / \mathrm{m} \cdot
\mathrm{K}\), (es \(\alpha_{s}=0.7\) ) of triangular cross section whose exposed
surface is subjected to solar heat flux of \(\dot{q}_{s}=\) \(800 \mathrm{~W} /
\mathrm{m}^{2}\) and to convection and radiation to the environment at
\(25^{\circ} \mathrm{C}\) with a combined heat transfer coefficient of \(30
\mathrm{~W} / \mathrm{m}^{2} \cdot \mathrm{K}\). The \(2-\mathrm{m}\)-high
vertical section of the dam is subjected to convection by water at \(15^{\circ}
\mathrm{C}\) with a heat transfer coefficient of \(150 \mathrm{~W} /
\mathrm{m}^{2} \cdot \mathrm{K}\), and heat transfer through the 2-m-long base
is considered to be negligible. Using the finite difference method with a mesh
size of \(\Delta x=\Delta y=1 \mathrm{~m}\) and assuming steady two-dimensional
heat transfer, determine the temperature of the top, middle, and bottom of the
exposed surface of the dam.