If you meant 4th or 5th edition (often miswritten as "47"), specify the problem numbers (e.g., "Chapter 4, Problem 7") and I can walk you through the concepts.
Dado que probablemente te refieres al o Problem 47 del capítulo de Transferencia de Momento, desglosamos la estrategia genérica. If you meant 4th or 5th edition (often