$41.$ True$/$False: The efficiency of gas$-$solid liquid contactors is independent of the phase distribution within the system.

$42.$ True$/$False: Estimating volume fractions in three$-$phase flows can be achieved through simple visual observation.

$43.$ True$/$False: Agitated vessels are inefficient for operations involving high$-$viscosity liquids.

$44.$ True$/$False: Optical imaging cannot be used to estimate volume fractions in multiphase flows.