An incompressible frictionless flow field is specified by the stream function \(\psi=-5 A x-2 A y\), where \(A=2 \mathrm{~m} / \mathrm{s}\), and \(x\) and \(y\) are coordinates in meters.

(a) Sketch the streamlines \(\psi=0\) and \(\psi=5\), and indicate the direction of the velocity vector at the point \((0,0)\) on the sketch.

(b) Determine the magnitude of the flow rate between the streamlines passing through \((2,2)\) and \((4,1)\).