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Dioxygen gas enters a $60$ mm $($internal diameter$)$ stainless steel pipe at $30\backslash$deg C and $10$ bar with an initial speed of $5$ m$/$s and exits this pipe $2$ meters lower at $30\backslash$deg C and $9$ bar. Calculate $$Ep $($in W$)$ assuming that dioxygen behaves like an ideal gas. Do not indicate your units.

Correct answer $=-3\mathrm{.}49$