Which of the following reveals the most common obstacle that engineers must overcome?

Acompressor receives the shaft work to decrease the pressure of the fluid. a)- true b)- false

Aflywheel accelerates for 5 seconds at 2 rad/s2 from a speed of 20 rpm. determine the total number of revolutions of the flywheel during the period of its acceleration. a.5.65 b.8.43 c. 723 d.6.86

The higher the astm grain size number, the finer the gran is. a)-true b)-false