In a small open economy, Desired national saving: 5% = $25 billion + ($150 billion) x r; Desired investment: / = $25 billion ($150 billion) x r*; Output: Y = $75 billion; Government purchases: G = $15 billion; World real interest rate: r* = 2%. a. Find the values of the following variables: (Round all answers to one decimal place. All values in billions of dollars.) National saving = $