Under flexible exchange rates and perfect capital mobility
a. monetary policy is ineffective while fiscal policy is very effective in changing the level of output
b. monetary and fiscal policy are both fairly ineffective in changing the level of output
c. monetary and fiscal policy have to be carefully coordinated if the level of output needs to be changed
d. monetary and fiscal policy are both very effective in changing the level of output
e. monetary policy is effective while fiscal policy is ineffective in changing the level of output"