Aggregate demand of economy refers to the total demand for goods and services in an economy at particular period of time.
A closed economy refers to one that has no imports or exports; in order words it is closed from foreign trade with other economies. Thus, fiscal policy would have a greater effect in this economy.
Open economy is the opposite of a closed economy; it allows foreign trade and the aggregate demand of the economy is better influenced by the monetary policy.
According to Mintzberg, Spokesperson is the person who is responsible for representing company on a public forum and is not associated with management of companies core operation.