a)Constract the use of electromechanical relaysagainst a PLC in the implementation of an automatic solution,giving the merits of using the PLC.
b) Two digital outputs y and z need to controlled as follows:
Y turns on if inputs x1 and x2 are high or if input x3 is low andinput x4 is high. Y stays on for 7s and then turns off, whilesimultaneously setting the output z to high. Z stays high for 5s,following which the sequence is repeated. The process is started bypressing a start pushbutton and is stopped by pressing a stoppushbutton.
Draw a ladder logic diagram to program a PLC for thisapplication.
