Why is a screw pump a quiet operating pump?

The temperature of air decreases as it is compressed by an adiabatic compressor. a)- true b)- false

Amixture of slurry and mud is to be pumped through a horizontal pipe of diameter 500 mm. the fluid behaves as a bingham plastic with a yield stress of 30 pa and viscosity 0.04 pa.s. describe the effects of the shear stress through a transverse section of the pipe by plotting the variation in shear stress and velocity profile: (i) just before the slurry starts to move (ii) as the slurry flows when the pressure gradient is double that in part (i)

How to increase the thermal officiency of an ideal simple rankino cycle? among these methods, which one is the best and why?