Please help with part 4 & 5 please show work!!!

Elon Motors Data: \begin{tabular}{lr|} \hline Cost of new equipment & $1,570,000 \\ \hline Expected life of equlpment in years & 12 \\ \hline Salvage Value & $70,000 \\ \hline Life Production & 36,000 \\ \hline Annual production or purchase needs & 3,000 \\ \hline Number of workers needed & 3 \\ \hline Annual hours to be worked per employee & 2,080 \\ \hline Eamings per hour for employees & $25.00 \\ \hline Health Benefits - % of Wages & 20% \\ \hline Cost of Direct Materials & $125.00 \\ \hline Variable Manufacturing Overhead Costs & $25.00 \\ \hline Unit Cost to Purchase Batterles & $325.00 \\ Required rate of return & 30% \\ \hline Tax rate & \\ \hline \end{tabular} Make Purchase Cost to Produce Annual cost of direct material: Need - Cost direct material for of 3,000 Batteries $375,000 Annual cost of direct labor for new employees: \begin{tabular}{|lr|} \hline Wages & 156,000 \\ \hline Health benefits & 31,200 \\ \hline Total wages and benefits & 187,200 \\ \hline \hline \end{tabular} Other variable production costs \begin{tabular}{r|} 75,000 \\ \hline$637,200 \\ \hline \hline \end{tabular} Annual Cost to Purchase Batteries Part 1 Cash Flows Over the Life of the Project Part 2 Payback Per 1,570,000/323,960 4.846 years Part 3 Accounting Rate of Return Accounting income as result of decreased costs Part 4 Net Present Value Net Present Value Part 5 Internal Rate of Return and Modified Internal Rate of Return Internal Rate of Return Modified Internal Rate of Return Net Present Value