(ii) List 62 factors that could contributed to the changes of pH in microbial fermentation process. Draw a two-dimensional schematic on how to realize a feedback control loop to control pH value in a stirred bioreactor system. Anaerobic process is a complex chain of subsequent and interacting degredation steps for production of a biogas. Biological monitoring and process control of such anaerobic process is highly important. Sketch an anaerobic digester schematic that includes the following features:- An open loop control of a pump for feed input to the reactor A feedback temperature control loop An online gas analyzer that is linked to the output of the digester