Do not only give the solutions, but also clearly explain your derivations.I need help please

Exercise 3 Consider an economy described by the circular flow model for a small open economy: Y Y C = C+c(Y -T) I = I-br NX = NX - d-E G G T T Y is aggregate production, C is private consumption, / is planned private investment, G is government purchases, T is taxes, and NX is net exports. r is the domestic real interest rate, r* is the foreign real interest rate, and & is the real exchange rate. C, I and /V X are autonomous consumption, autonomous investment and autonomous net exports, respectively. c, b and d are parameters, with 0 0 and d > 0. Y, C, I, NX, G, T, c, b, d and r* are exogenous. Assume for all your computations that the goods market is in equilibrium. Assume the following functional forms and parameter values: Y = 300, G =60, T=40, r* = 5 C = 20+ 4(Y -T) I = 100 - 10r NX = 140- 10 Compute now the equilibrium values of the following variables: 1. private saving Spr 2. public saving Spub. 3. total saving S. 4. planned private investment I. 5. the real interest rate r