Following the lead of given example, design an optimum 2-bit quantizer for a signal whose samples follow a triangular PDF,
(a) Find the four quantization levels 
and the three boundary points, 
(b) Find the mean-squared distortion, d .
(c) Find the signal-to-quantization-noise ratio in dB.
Example
An exponential random variable has a PDF given by
(a) Find the mean and variance of X .
(b) Find the conditional mean and the conditional variance given that X > 1 .