<prompt> Translate the following text to EnglishUtafiti wa mwisho wa ubora wa hewa ya mafuta ya dizeli ya injini nzito, mbinu zilizochaguliwa za faida za afya na ustawi, na matokeo ya uchambuzi wa faida.  <response>: Final Heavy-Duty Engine Diesel Fuel Air Quality Estimation, Selected Health and Welfare Benefits Methods, and Benefit Analysis Results. 