The number of telephone calls that arrive at a call center is often modeled as a poisson random variable. Assume that on the average there are 10 calls per hour If the operators of the call center take a 30 minutes break for lunch what is probability that they don’t miss any call ?

The mass flow rate of the fluid remains constant in all steady flow process. a)- true b)- false

Refrigerant 134a enters an insulated compressor operating at steady state as saturated vapor at -26°c with a volumetric flow rate of 0.18 m3/s. refrigerant exits at 9 bar, 70°c. changes in kinetic and potential energy from inlet to exit can be ignored. determine the volumetric flow rate at the exit, in m3/s, and the compressor power, in kw.

Which of the following refers to refers to how well the control system responds to sudden changes in the system. a)-transient regulation b)- distributed regulation c)-constant regulation d)-steady-state regulation