4.8 Find the phasors for the following field quantities: (a) E,(z. t)= E, cos (out-Bz+6) (V/m) (b) E,(2,1)= 100e cos (at - 5z + m/4) (V/m) (c) H.(t) = H, cos

(tot + Bz) (A/m) (d) H,(z. t) = 120me cos (wt+Bz+ b) (A/m)