$41.$ Atmospheric and vacuum distillation processes are key to refining, focusing on the separation of $\_\_\_\_$ fractions and processing of $\_\_\_\_$ residues, respectively, to optimize product $\_\_\_\_.$

$42.$ The degree of separation, particularly measured by the $5-95$ gap, is critical for determining the $\_\_\_\_$ and $\_\_\_\_$ of the distillation process, influencing $\_\_\_\_$ adjustments.

$43.$ A refinery's use of Packie charts can lead to better distillation $\_\_\_\_$ decisions, enhancing product $\_\_\_\_$ and operational $\_\_\_\_.$

$44.$ Desalting not only improves the quality of crude oil by removing $\_\_\_\_$ and $\_\_\_\_,$ but also protects $\_\_\_\_$ units from corrosion and $\_\_\_\_.$