Table $1.($Note: Notation used in the Table follows from the lectures$)$

Using the values in the table above, answer the following questions. $($Show your work$)$

a$)$ Derive the expression for the IS curve $($i$.$e$.,\backslash (\backslash$boldsymbol$\{$Y$\}\backslash )\backslash (=$f$($r$))\backslash )$

$(3$ points$)$

b$)$ If the real interest rate is $4\backslash \%,$ what is the value of equilibrium real GDP $($Y$)?$

$(2$ points$)$