This macroeconomics assignment delves into key economic models and concepts. It begins with multiple-choice questions covering GDP, business cycles, output gaps, the Keynesian multiplier, and the effectiveness of fiscal and monetary policies. The assignment then explores the Keynesian model, calculating equilibrium output and analyzing the impact of government spending. Furthermore, it utilizes the IS-LM model to examine the effects of demonetization and fiscal policies on output and interest rates. The assignment also uses the AD-AS model to analyze deflation, the Phillips curve, and the drivers of inflation. The solution provides detailed explanations and calculations, offering a comprehensive understanding of macroeconomic principles and their applications.