8-3. Given the second-order digital-filter transfer function D(z) == 2z² 22 - 2.4z+0.72 1.4z+0.98 (a) Find the coefficients of the 3D structure of Fig. P2.8-1 such that D(z) is realized. (b) Find the coefficients of the ID structure of Fig. P2.8-1 such that D(z) is realized. (k) (k) T Bo xk) (a) by FIGURE P2.8-1 Digital-filter structures: (a) 3D; (b) 1D. (b) by do y(k)