¿A qué se denomina costo de oportunidad? ¿Qué es el crecimiento económico desde esta perspectiva?

What is called opportunity cost? What is economic growth from this perspective?

First of all we may refer to the things in classroom in spanish as both los artículos del aula de clases  and los objetos de la clase  we will begin by looking at a picture containing several of these items. we will see them in sentences later to hear  their pronunciation and how they could be used in real contexts