What is NOT an example of professional networking?

Which from the following instrument is commonly used to detect the high pitch butzing sound in bearings? [clo4] a)-digital ultrasonic meter b)-infrared camera c)-spectroscopic d)-vibrometer

What is the heat treatment of metals? what is the benefit of it? why and how it's useful? answer in details, do not write by hand.

Consider two concentric spheres forming an enclosure with diameters of 12 cm and 18 cm the spheres are maintained at uniform temperatures ti-50°c and t2 = 250°c and have emissivities .45 and .8, respectively. determine the net rate of radiation heat transfer between the two spheres per unit surface area.