1. Figure in the below presents the direct form II realization of a difference equation. Assume that the resulting system is linear and time-invariant. x[n] v[n] y[n] 1/3 -2 a) Find the direct form I realization. b) Find the difference equation described by the direct form I realization. c) Find the relation between v[n] and y[n]. Find the relation between v[n] and x[n]. Using these relations, verify that the relation between y[n] and x[n] in the direct form II realiza- tion is the same as your answer to part (b).