$7\mathrm{.}5$ Figure $7\mathrm{.}14$ shows a setup to determine the energy loss due to a certain piece of apparatus. The inlet is through a $2-$in Schedule $40$ pipe and the outlet is a $4-$in Schedule $40$ pipe. Calculate the energy loss between points A and $B$ if water is flowing upward at $0\mathrm{.}006\frac{m^3}{s}.$ The gage fluid is mercury