Final answer:
The subject of this question is Physics. It relates to the study of 2D incompressible viscous flow in the context of Poiseuille flow.
Step-by-step explanation:
The subject of this question is Physics. It relates to the study of 2D incompressible viscous flow in the context of Poiseuille flow. Poiseuille's law describes laminar flow of an incompressible fluid through a tube, with flow rate and pressure difference being directly proportional and flow rate increasing with the fourth power of the radius.