5. Signal Properties - Energy/Power (a) (2 pts) Find the energy E∞ and power Po of the signal x(t) = cos² (3t). Is this an energy signal or a power signal? Show that x(t) has infinite energy but finite power with P∞ = is a power signal. The power of a periodic signal can be calculated from the power in one period. so hence it (b) (2 pts) Find the energy E∞ and power P∞ of the signal x(t) = u(t + 2) = u(t - 3). Is this an energy signal or a power signal? Show that x(t) has zero power but finite energy with E∞ = 5, so hence x(t) is an energy signal. (c) (5 pts) Find the energy E∞ of the signal x(t) = e−3tu(t + 1). Is this an energy signal or not?