Specific language impairment (SLI) is diagnosed when a child's language does not develop normally and the difficulties cannot be accounted for by generally slow development, physical abnormality of the speech apparatus, autism spectrum disorder, acquired brain damage or hearing loss.
Perfect competition. A perfectly competitive market is a hypothetical market where competition is at its greatest possible level. Neo-classical economists argued that perfect competition would produce the best possible outcomes for consumers, and society.
Pure monopoly exists when a single firm is the sole producer of a product for which there are no close substitutes. Examples are public utilities and professional sports leagues, Characteristics 1. A single seller: the firm and industry are synonymous. 2. Unique product: no close substitutes for the firm s product. 3. The firm is the price maker: the firm has considerable control over the price because it can control the quantity supplied. 4. Entry or exit is blocked. Barriers to Entry Economies of scale is the major barrier.