Water flows steadily through the $0\mathrm{.}75$ in$.-$diameter galvanized iron pipe system shown below at a rate of $0\mathrm{.}020$ cfs $.$ Your boss suggests that friction losses in the straight pipe sections are negligible compared to losses in the threaded elbows and fittings of the system. Do you agree or disagree with your boss? Support your answer with appropriate calculations. $($Note: use Moody diagram to find the friction factor; the $K_L$ for the $90$ elbow, tee, and reducer are $1\mathrm{.}5,2\mathrm{.}0$ and $0\mathrm{.}15$ respectively$).[30$ pts $]$