Please show me step by step on how to compute pyback and can you please give me step by step instruction on how to do question 2 thank you

Your company is considering two mutually exclusive investment projects, each of which requires an upfront expenditure of $15 million. You estimate that the investments will produce the following net cash flows. Assume your cost of capital is 16%. 2. Using the data from the above analysis, compute the crossover point for the two projects