How to solve this advanced macroeconomics theory question?

Thank you for the help

3. [14 marks total] [u this question, we consider what happens when the household facm both a spread between borrowing and saving interest rates and a. borrowing constraint at the same time. That is, we consider the household problem as stated just before the beginning of Section 1.1 of LNE: maximise equation [4} subject to the constraints {1], [3}, and {5}. Assume throughout that r3 3: r3 {strictly positive spread] and I] a: if: 4:: ti\