Using AS-AD diagrams, illustrate each of the following economic situations by showing the patterns and shifts of either AS or AD that could cause them to happen: a. a rise in the price level triggered by higher oil prices; b. a rise in inflation that happens four years in a row because government spending keeps increasing; c. foreign investors gain confidence and increase the level of investment in the U.S. economy; d. the economies of trading partners grow very slowly, leading to a decrease in exports to those countries e. output declines slightly but the price level falls a great deal.