The figure below shows the application of electric components and devices in oil and gas applications.Based on what you have studied on interfacing circuits and control devices (chapter 7). How can you control the motor's rotational speed (specifically the motor shown in the figure below)? a) Name the electric device that can control the motor rotational speed, and b) What are the parameters that can be controlled to control the motor rotational speed?

Fig: 1

Fig: 2

Fig: 3

Fig: 4