Consider a small open economy with desired national saving of \(S^{d}=30+200 r^{w}\) and desired investment of \(I^{d}=30-200 r^{w}\).

Calculate national saving, investment, and the current account balance in equilibrium when the real world interest rate is

a. \(r^{w}=0.025\).

b. \(r^{w}=0.05\).

c. \(r^{w}=0.0\).

d. Now suppose something causes desired national saving to increase by 10 , so that it is now \(S^{d}=30+200 r^{w}\). Repeat parts (a), (b), and (c).

\(e\). Suppose, with desired national saving at its original level of \(S^{d}=20+200 r^{w}\), something causes desired investment to rise by 10 , to \(I^{d}=40-\) \(200 r^{w}\). Repeat parts (a), (b), and (c).