consider the following three system functions corresponding to casual LTI systems:...

consider the following three system functions corresponding to casual LTI systems:

(a) For each system function, draw a direct-form block diagram.

(b) For each system function, draw a block diagram that corresponds to the cascade connection of two second-order block diagrams. Each second-order block diagram should be in direct form.

(c) For each system function, determine whether there exists a block diagram representation which is the cascade of four first-order block diagrams with the constraint that all the coefficient multipliers must be real.