Each of the following events caused a shift in the AD or AS curve in Canada. Identify which curve was affected and describe the effect on equilibrium real GDP and the price level.

a. OPEC’s actions to restrict oil output significantly increased the world price of oil in 1979–1980.

b. World commodity prices increased sharply from 2002 to 2008. Many of these commodities are both produced in Canada and used as important inputs for Canadian firms.

c. The end of the Cold War in 1990 led to large declines in defence spending in many countries (including Canada).

d. The federal government and (many) provincial governments reduced corporate income-tax rates between 2000 and 2015.

e. The federal government increased its level of government purchases (G) in 2009 and 2010, amidst a global recession.

f. The beginning of a strong recovery in the United States in 2014 led to a large increase in the demand for many Canadian exports.

g. The world price of oil fell from U.S. \($105\) per barrel in June 2014 to U.S. \($50\) in February 2015.

h. The possible cancellation of the North American Free Trade Agreement led many Canadian firms to reduce desired investment in 2017 and 2018.