You are evaluating the sensitivity of tax rate on the economic assessment of a new production dozer. The dozer will require an initial investment of $1.9 million, but will provide $598,708 in revenue for each of the next 10 years. O\&M costs are $231,740 per year. Depreciation is the only book deduction and can be calculated using the straight line method assuming no salvage value and a useful life of 10 years. Based on this information, what is the maximum income tax rate that can applied while maintaining a minimum attractive rate of return of 10%