Which one of the following statements is true for fully developed flow through pipes?
(a) The flow is parallel, has no inertial effects, the pressure gradient is of constant value and the pressure force is balanced by the viscous force
(b) The flow is parallel, the pressure gradient is proportional to the inertia force and there is no viscous effect
(c)The flow is parallel, the pressure gradient is negligible and the inertia force is balanced by the viscous force
(d) The flow is not parallel, the core region accelerates and the viscous drag is far too less than the inertial force