Stuck on these two ?

First one:

(Advanced Analysis) Assume the consumption schedule for a private open economy is such that consumption is as follows: C = 50 + .80 Y Assume further that planned investment lg and net exports Xn are independent of the level of real GDP and constant at: I9 = 30 Xn =10 Recall also that, in equilibrium, the real output produced (Y) is equal to aggregate expenditures: Y: C + Ig+ Xn. a-1. Calculate the equilibrium level of income or real GDP for this economy? $ a-2. Check your work by expressing the consumption, investment, and net export schedules in tabular form and determining the equilibrium GDP. Aggregate Kn expenditures H In Real GDP 2 00 250 300 350 400 450 500 550 600 650 Wt! |||||||||| WED ||||||||||| b. What happens to equilibrium Yif lg changes to 10 ? v=$- What does this outcome reveal about the size of the multiplier? The multiplier = (2) (6) (1) Real Domestic Aggregate (3) (4) (5) Aggregate Net Output Expenditures, Exports, Import, Expenditures, (GDP = DI) , Private Closed Billions Billions Exports, Private Open Billions Economy, Billions Billions Economy , Billions $200 $240 $20 $30 $ -10 230 $ 250 $280 $20 $30 un -10 270 $300 $320 $20 $30 $ -10 $ 310 $ 350 $360 $20 $30 $ -10 -ur 35( $400 $400 $20 $30 $ .10 $ 390 $ 450 $440 $20 $ 30 -10 $ 430 $500 $480 $20 $30 $ -10 $ 470 $550 $520 $20 $30 $ 10 510 a. Use columns 1 and 2, what the equilibrium GDP for this hypothetical economy? $|400 billion Instructions: Enter a whole number for your answer. b. Now open up this economy to international trade by including the export and import figures of columns 3 and 4. Fill in columns 5 and 6. What is the equilibrium GDP for the open economy? $ billion What is the change in equilibrium GDP caused by the addition of net exports? $ billion c. Given the original $20 billion level of exports, what would be the equilibrium GDP if imports were $10 billion greater at each level of GDP? Net exports = $[ billion Equilibrium GDP = $ billion d. What is the multiplier in this example, assuming no change in consumption or investment