A duct $0\mathrm{.}4$m high and $0\mathrm{.}8$ m wide bends horizontally at a right angle with inner radius and outer radius at $0\mathrm{.}2$m and $1\mathrm{.}0$m respectively measured from the common center. Air velocity in the duct is $12$ m$/$s$.$ a$.$ Sketch the set up showing the necessary measurements. b$.$ Determine the pressure drop in the duct bend? c$.$ Determine the equivalent of a straight duct corresponding to the pressure loss in the duct bend.