Write the word or phrase that best completes each statement or answers the question. The above figure shows the AE curve and 45" line for an economy. a. If real GDP equals $6 trillion, how do firms' inventories compare to their planned inventories? b. If real GDP equals $12 trillion, how do firms' inventories compare to their planned inventories? c. What is the equilibrium level of expenditure? Why is this amount the equilibrium? Aggregate planned expenditure [trillions of 2000 dollars) 15 45" line 12 AE 9 12 Real GDP (trillions of 2000 dollars]