Problem $1$ Recreate the cash flow spreadsheet provided in Table $6\mathrm{.}6$ and reproduce the results. a$)$ In what year do you first see a positive cash flow? b$)$ What is the present value of the cash flow in year $14?$ c$)$ What NPV do you get when you set the discount rate to be the same as the IRR? d$)$ Eliminate the down payment and see what happens to the IRR. Then try paying for the whole system with cash. Again, compare IRR and comment e$)$ Find the NPV and IRR for a $\backslash (4-\backslash$mathrm$\{$kV$\}\backslash )$ system in an area with $\backslash (5\mathrm{.}5-\backslash$frac$\{$k W h$\}\{$m$^\{2\}$ d$\}\backslash )$ insolation, using a derating of $0\mathrm{.}72.$ Keep everything else the same TABLE $6\mathrm{.}6$ Cash Flow Analysis for the Silicon Valley PV System