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I need 2 paged answer

Explain the long (buy) and short positions required to take advantage of the momentum (Jegadeesh and Titman, 1993) investment strategy. Discuss alternate explanations provided in the academic literature to explain the momentum effect. What are the components of transaction cost when buying and short-selling shares? Which factors may influence the magnitude of such costs? Which is the theoretical advantage of short-selling stocks when following the momentum strategy?