Can you help with the red boxed question, it got me confused!

This is what I have got from the first part of the question

Can you PLEASE help and give some explanation.Also, try to demonstrate in excel if possible.

Thank you!

Consider a mining and processing project for an oil tar sands project. From the data given below, calculate the after-tax cash flows for a 30-year life of the project and the NPV for an MARR of 15% Initial capital expenditures totaled $415.5 million and were distributed over four years (10% in year 0,30% in year 1, 40% in year 2, and 20% in year 3). Beginning in year 4: 17.666 million tons of ore will be mined per year -Bitumen production rate will be 7.347 million barrels per year -Product yield will be 0841 barrels of oil per barrel of bitumen -Product selling price will be $80 per bamel -Operating costs: $10.47 per barrel of bitumen for plant and upgrading costs $9.02 per ton of ore for mining costs -10-year straight-line depreciation -4% tax rate (state and federal) After completing the analyses determine the sensitivity of a possible reduced selling price of the product on the profitability (rate of return) of the project. Perform this analyses in 10% increments until the project does not produce a rate of return that meets the MARR. At each increment of reduction in selling price what production increase will be required to maintain the profit margin achieved at $80 per barrel. Place your sensitivity analyses on a separate tab from the NPV analyses of your excel file. Include graphics/excel charts to summarize your analyses and conclusions Consider a mining and processing project for an oil tar sands project. From the data given below, calculate the after-tax cash flows for a 30-year life of the project and the NPV for an MARR of 15% Initial capital expenditures totaled $415.5 million and were distributed over four years (10% in year 0,30% in year 1, 40% in year 2, and 20% in year 3). Beginning in year 4: 17.666 million tons of ore will be mined per year -Bitumen production rate will be 7.347 million barrels per year -Product yield will be 0841 barrels of oil per barrel of bitumen -Product selling price will be $80 per bamel -Operating costs: $10.47 per barrel of bitumen for plant and upgrading costs $9.02 per ton of ore for mining costs -10-year straight-line depreciation -4% tax rate (state and federal) After completing the analyses determine the sensitivity of a possible reduced selling price of the product on the profitability (rate of return) of the project. Perform this analyses in 10% increments until the project does not produce a rate of return that meets the MARR. At each increment of reduction in selling price what production increase will be required to maintain the profit margin achieved at $80 per barrel. Place your sensitivity analyses on a separate tab from the NPV analyses of your excel file. Include graphics/excel charts to summarize your analyses and conclusions