$41.$ 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 $\_\_.$