3. Design and draw a circuit using the cascade system to operatetwo cylinders (A and B) which, on the operation of a start valve,produces the sequence A – B + B – A+. The cylinders should park inthe positions B – A + when the start switch is in the ‘off’position.
4. Modify the circuit designed for question 3 to provide anemergency stop which will park both cylinders in the extendedposition (i.e. A + B +).
5. Modify the circuit designed for question 3 to provide a failsafe. The fail safe should:
(a) act in the event of a reduced pressure at inlet to the groupselecting valve
(b) park the cylinders in the retracted position
