Discuss In 2-3 paragraphs (see getting started module for details, including the specific sentence length requirements), respond to the following. Your initial post should be substantive. Also reply to at least 2 classmate's posts. Offer a substantive reply of at least 1 paragraph. Aim to complete your initial post by Thursday of each week to allow other students to respond before Friday. Discuss the importance of AS-AD models in explaining macroeconomic conditions of the economy and business cycles. What factors shift the AS-AD curves? How do you explain the performance of the economy (macroeconomic fluctuations) during the last few years using the AS-AD model? What has happened to aggregate demand? What evidence can you present to support this position