Did the decline in the price of oil cause a shift in the aggregate supply curve or the aggregate demand curve?

Explain what the effect will be on quantity and price.
December 24, 2020
Did the financial crisis raise the equilibrium price level, lower the equilibrium price level, or have an ambiguous effect?
December 24, 2020

From 2014 to 2015, the average price of crude oil plunged from $100 per barrel to $50 per barrel.  a) Did the decline in the price of oil cause a shift in the aggregate supply curve or the aggregate demand curve? b) Draw an aggregate supply–aggregate demand diagram to illustrate the impact of the oil price decline. Label the original aggregate equilibrium and the new aggregate equilibrium. Does output Q rise or fall?