If the Firm A is having a monopoly in the production of X we can assume that the Firm A is producing at a level of output which is marginal cost equals marginal revenue.
This is a situation that exists in a market where there is a single producer or seller of a product. The monopolist has no competitors.
Due to this he enjoys unfair advantages and can set the price in the market to any level that he wants.
Read more on monoploy here: https://brainly.com/question/7217942