Water flows in a constant-diameter pipe with the following conditions measured: At section

(a) \(p_{a}=32.4 \mathrm{psi}\) and \(z_{a}=56.8 \mathrm{ft}\); at section

(b) \(p_{b}=29.7 \mathrm{psi}\) and \(z_{b}=68.2 \mathrm{ft}\). Is the flow from (a) to (b) or from (b) to (a)? Explain.