Consider the signal x (t) = 10+ 20 cos (100*2 t + 4) + 10 cos (250*2 t ) A. Using Euler's relation, the signal x(t) defined by the above equation can be expressed as a sum of complex exponentials in the form X(t) = x0 + Re{k=1N Xkejk2fot} What is w0, and what are the values of Xk It is not necessary to evaluate any integrals to obtain Xk. B. is the signal x(t) periodic If so, what is the period? C. Plot the spectrum of this signal.