What method(s) can Chris use to make sure the segments in the pattern are all parallel and that his new trusses are built precisely and strongly

At steady state, air enters an insulated duct of varying cross-sectional area (similar to a nozzle or diffuser) at 200 kpa, 52°c with a mass flow rate of 0.5 kg/s. at the duct exit, the pressure of the air is 100 kpa, the velocity is 255 m/s, and the cross-sectional area is 2 x 10-3 m^2. assuming an ideal gas model, determine: a)-find the specific volume of the air at the exit, in m3/kg. b)- the temperature of the air at the exit, in k. c)-the velocity of the air at the inlet, in m/s. d)-the inlet cross-sectional area, in m^2.