Consider the IS-LM model of the open economy and explain whether each of the following statements is true or not, and why. Make sure to highlight the channel or channels through which each policy change will affect output in the short run, according to the model. a) A fiscal expansion is more effective at boosting output in the short run if the economy's exports and imports each constitute 80% of its GDP than if they constitute 20% of GDP. b) A fiscal expansion is more effective at boosting output in the short run if the economy's trading partners are also enacting similar fiscal stimulus programs than if the country is the only one with a fiscal expansion package at this time. c) A monetary expansion is more effective at boosting output in the short run if the economy's exports and imports each constitute 80% of its GDP than if they constitute 20% of GDP. d) A monetary expansion is more effective at boosting output in the short run if the economy's trading partners are also enacting similar monetary expansions than if the country is the only one cutting its policy rate at this time