$8\mathrm{.}14$ Water flows in a constant$-$diameter pipe with the following conditions meassured: At section $($a$)p_a=32\mathrm{.}4$ and $z_a=56\mathrm{.}8ft$; at section $($b$)p_b=29\mathrm{.}7$ and $z_b=68\mathrm{.}2ft.$ Is the flow from $($a$)$ to $($b$)$ or from $($b$)$ to $($a$)?$ Explain.