3. If for a perfectly competitive firm, price is Rs. 60, output is 300 units, average variable costs are Rs. 18, and average total costs are Rs. 36. The firm's profits are equal to
7. __________ says that if we keep increasing the employment of an input, with other inputs fixed, eventually a point will be reached after which the resulting addition to output (i.e., marginal product of that input) will start falling.
9. In a market system, the central problems regarding how much and what to produce are solved through the coordination of economic activities brought about by ________ signals.
10. The study of individual markets of demand and supply in which the 'players', or the decision makers, were also individuals (buyers or sellers, even companies) who were seen as trying to maximize their profits (as producers or sellers) and their personal satisfaction or welfare levels (as consumers) is called?