$4.$ A Canadian firm is evaluating an investment in Indonesia. The project costs $500$ billion Indonesian Rupiah and is expected to produce an income of $250$ billion Indonesian Rupiah in a year in real terms for each of the next three years. The expected inflation rate in Indonesia is $12\%$ per year. And the firm estimates that an appropriate discount rate for the project would be about $8\%$ above the risk$-$free rate of interest. Calculate the net present value of the project in dollars. Assume a spot rate exchange rate of $$0\mathrm{.}000112/$ Rupiah. The interest rate is about $15\%$ in Indonesia and $5\%$ in Canada. Could you please show how to calculate this in excel?