distance travelled per unit length

distance travelled per unit time

distance travelled per unit pressure

distance travelled per unit temperature

331.2 m/s

300 m/s

250 m/s

230 m/s

temperature and pressure

surface area and volume

temperature and composition

composition and surface area

compressible flow

incompressible flow

turbulent flow

rotational flow

sonic flow

subsonic flow

supersonic flow

any of the mentioned

the square root of the ratio of the inertia force to pressure force

 the square root of the ratio of the inertia force to an elastic force

 the square root of the ratio of the inertia force to surface tension force

 the square root of the ratio of the inertia force to buoyancy force

zone of action

zone of silence

control volume

none of the above

$\sin \alpha =\frac{1}{M}$

$\mathrm{sin\alpha }=\mathrm{M}$

$\mathrm{sin\alpha }={\mathrm{M}}^2$

$\mathrm{sin\alpha }={\mathrm{M}}^3$

twice of the angle of Mach cone

half of the angle of Mach cone

equal to the angle of Mach cone

none of the mentioned

velocity increases

velocity decreases

remains constant

unpredictable