Let x[n] be a real stationary white-noise sequence, with zero mean and variance . Let...

Let x[n] be a real stationary white-noise sequence, with zero mean and variance . Let x[n] be the input to the cascade of two causalLTI discrete-time systems, as shown in Figure P2.93.

(c) Let h₁[n] = aⁿu[n] and h²[n] = bⁿu[n]. Determine the impulse response of the overall system in Figure P2.93, and, from this, determine . Are your answers to parts (b) and (c) consistent?