How do the compressible-pipe-flow formulas behave for small pressure drops? Let air at 20C enter a tube

Question:

How do the compressible-pipe-flow formulas behave for small pressure drops? Let air at 20°C enter a tube of diameter 1 cm and length 3 m. If f = 0.028 with p1 = 102 kPa and p2 = 100 kPa, estimate the mass flow in kg/h for
(a) Isothermal flow,
(b) Adiabatic flow, and
(c) Incompressible flow (Chap. 6) at the entrance density.