2. For the following 4-node quadrilateral elements (given in terms of phys. coords.) below: draw the elements, compute the isoparametric map (i.e., x and y as functions of έ and n), the Jacobian matrix, and the determinant of the Jacobian. For what values of -1<<1 and -1<<1 (if any) are the determinants of the Jacobians negative? (a) 1:(0,0), 2:(1,0), 3:(2,2), 4:(0,1) (b) 1:(0,0), 2:(4,0), 3:(1,1), 4:(0,4) Finally, use Matlab to plot a 2D x-y grid using the map functions for a range of values of -1<<1 and -1≤1. (Hint: use the meshgrid and mesh functions and a point spacing of 0.25)