Regarding the carbon-to-nitrogen ratio issue

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It is well known that a carbon-nitrogen ratio of 100:5 is the most suitable, but there are still some aspects that are not entirely clear, so I would like to ask for advice. The carbon-nitrogen ratio we are referring to is the optimal one required for bacterial growth in sludge. Now, here are the questions: 1. Carbon removal occurs through three processes – first, through the assimilation by microorganisms; second, through the adsorption of organic matter by microorganisms followed by its removal via excess sludge; and third, through microbial respiration to meet energy needs. What proportion does each of these processes account for in municipal wastewater? 2. The removal of nitrogen also occurs in 3 ways: first, through assimilation; second, by microorganisms absorbing the excess sludge and then excreting it; third, through the nitrogen consumed in nitrification and denitrification processes. In fact, this last process is also a form of respiration that provides the heat required by the sludge. So, what proportion does each of these three methods account for? 3. After ensuring a ratio of 100:5 required for assimilation, the sludge needs to undergo denitrification; therefore, how much carbon source is needed, and what ratio between BOD carbon and total nitrogen is required to meet the removal standards?