I've attempted this question multiple of times and my answers are wrong compared to the memo and I still couldn't get help from other tutors since this is outside their expertise.

Vibration monitoring this technique uses the noise or vibration created by mechanical equipment and in seme cases by plant systems to detemine their actual condtion. a)- true b)- false

Afan that can provide air speeds up to 60 m/s is to be used in a low-speed wind tunnel with atmospheric air at 35 c. if one wishes to use the wind tunnel to study flat-plate boundary layer behavior up to reynolds numbes of re 10, what is the minimum plate length that should be used? at what distance from the leading edge would transition occur if the critical reynolds nurnber were rer,e = 5 × 105?

Around steel bar, made from material with a yield stress of 750mpa, is loaded so that it has stresses co locations of maximum normal stress and maximum shear stress. use maximum shear stress and maximum distortion energy theories to calculate the safety factors for initial yielding failures.