The \(y\) component of velocity in a two-dimensional incompressible flow field is given by \(v=-A x y\), where \(v\) is in \(\mathrm{m} / \mathrm{s}\), the coordinates are measured in meters, and \(A=1 \mathrm{~m}^{-1} \cdot \mathrm{s}^{-1}\). There is no velocity component or variation in the \(z\) direction. Calculate the acceleration of a fluid particle at point \((x, y)=(1,2)\). Estimate the radius of curvature of the streamline passing through this point. Plot the streamline and show both the velocity vector and the acceleration vector on the plot. (Assume the simplest form of the \(x\) component of velocity.)