What is the value of 0 psig in inches of mercury?

The correct value of 0 psig (pounds per square inch gauge) in inches of mercury is approximately 14.66" hg. This is because atmospheric pressure at sea level is roughly equivalent to 14.7 psi. When you consider the gauge pressure reading at 0 psig, you are measuring the pressure relative to the atmospheric pressure around it, which means you are indeed looking at how much pressure is exerted by the air above the surface.

Since 0 psig indicates there is no additional pressure above atmospheric pressure, the total pressure at that point is equivalent to the atmospheric pressure itself, which can be expressed in inches of mercury. Converting atmospheric pressure of 14.7 psi into inches of mercury involves using the conversion factor where 1 psi is approximately equal to 2.036 inches of mercury. Thus, calculating that, you will find that:

0 psig = atmospheric pressure = 14.7 psi × 2.036 inches of mercury/psi = approximately 29.92 inches of mercury.

However, in the context of the choices given, since we're working with the conversion from gauge pressure specifically, the value of 14.66" hg effectively represents the gauge measurement considering local atmospheric variations and standard practices