A and B please

6. The E-field vector of a vertically linearly polarized electric field can be written AS E(z, t) = izEo cos(kz - wt). (1) How can we write the E(z, t) of an electric field that is (a) circularly polarized? [1 pt.] (b) linearly polarized at 45 (Fig. 2.2(c) in the textbook)? [1 pt.]