Question 2 (4 points) How is the PLC-controlled system similar to the hard-wired relay control system? How is it different? Question 3 (4 points) The most basic type of real-world input to a PLC is a discrete (on/off) input. Each discrete input channel on a PLC is associated with a single bit in the PLC's memory. Based on our discussion in this class, what does a "1" bit status signify, and what does a "0" bit status signify? Question 6 (2 points) What is the difference between a counter and a timer in PLC ladder logic? Question 7 (3 points) Identify two realistic applications for PLC programs using counters and timers. What sorts of real-life processes might benefit from a PLC function where something turns on or off after a definite number of counts applied to the PLC input, or after a certain amount of time has passed?