How can economics or diseconomics of ...

It is very simple. You can apply your common sense to analyze this problem. Firstly you have to consider what kind of industry it is. Whether it produces food,electronic appliance, or medicine and so on. Secondly you have to know whether such industry exists in local market or global market. Knowing the demand for the goods produced can also help you know what kind of scale it should be. For example, a local baker produces hotdogs for the people living nearby. The demand for the bread is limited. Lets say people there only need 100hotdogs, but if u produce 1000, the extra wont be sold. In this case, the hotdog seller can choose to expand its shop by purchasing more baking machine instead of hiring workers in order to increase production and reduce marginal cost as well, but if he does so, the extra bread wont be sold. Therefore it cannot reap up ecnomics of scale, but have to stay small. In another case of a big MNC like Macrosoft, it owns 90% of the PC shipments in the world. Such