Suppose an economy is depicted by the expenditure function provided​ below: C​ + G​ + I​ + X​ = ​$300 ​+ 0.80timesY ​+ ​$350 ​+ ​$275 ​+ ​$75 All figures are in billions of dollars. Assume there are no taxes in this nation so disposable income Yd​ = Y. The economy reaches an equilibrium at ​$ nothing billion. ​(Enter your answer as a whole​ number)