$1.$ What does the drift flux model primarily describe in multiphase flow?

A$)$ The velocity of one phase relative to the mixture velocity

B$)$ The pressure drop across the flow

C$)$ The temperature distribution within the flow

D$)$ The chemical reaction rate between phases

$2.$ In the context of the drift flux model, what is the void fraction?

A$)$ The fraction of the pipe that is empty

B$)$ The volume fraction of the gas phase

C$)$ The volume fraction of the liquid phase

D$)$ The fraction of solid particles in the flow

$3.$ Which of the following best describes bubbly flow?

A$)$ A flow regime with distinct large gas bubbles

B$)$ A flow regime where liquid droplets are dispersed in gas

C$)$ A flow regime characterized by small, dispersed gas bubbles in liquid

D$)$ A solid$-$liquid flow with minimal interaction between phases

$4.$ What modification is typically required for the drift flux model when applied to mini channels?

A$)$ Increased surface tension effects

B$)$ Decreased gravitational impact

C$)$ Increased viscosity effects

D$)$ Decreased interfacial tension